Merge ~paride/curtin:pylint-explicit-generated-members into curtin:master

[Paride Legovini]

pylintrc: explicitly list the DISTROS generated-members

For some obscure reason setting

  generated-members=DISTROS\.

in pylintrc makes the pylint run flaky, causing failures like:

curtin/commands/install_grub.py:93:19:
  E1101: Instance of 'Distros' has no 'debian' member (no-member)
curtin/commands/install_grub.py:155:28:
  E1101: Instance of 'Distros' has no 'redhat' member (no-member)

These failures:

 - happen on about 15% of the time, at least on Bionic
 - also happen with the latest stable version of pylint (2.8.2)
 - only happen on install_grub.py (which only refers to debian and redhat)
 - do not seem to happen on Impish.
 - possibly related: https://github.com/PyCQA/pylint/issues/1628

But the truth is I don't understand why generated-members=DISTROS\.
even works some of the time for some generated members. Let's replace
it with the explicit list of the (non auto-detected) generated members,
so it will always work, and we'll know why it does.

[Paride Legovini (paride)]

See the commit message for rationale and reasoning.

I'd be very happy to amend the last paragraph if anybody can explain why

  generated-members=DISTROS\.

kind of works.

[Dan Bungert (dbungert)]

I am able to repro the issue as listed (approx 15%) with a loop around "tox -e py3-pylint" with a host machine amd64 hirsute.

The attached change works around that flakiness reliably for me.

review: Approve

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:101acb8c274c2de0e4f0a6758aa38bcc4813dca7

No commit message was specified in the merge proposal. Click on the following link and set the commit message (if you want jenkins to rebuild you need to trigger it yourself):
https://code.launchpad.net/~paride/curtin/+git/curtin/+merge/402652/+edit-commit-message

https://jenkins.ubuntu.com/server/job/curtin-ci/123/
Executed test runs:
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-amd64/123/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-arm64/123/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-ppc64el/123/
    FAILURE: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-s390x/123/

Click here to trigger a rebuild:
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review: Needs Fixing (continuous-integration)

[Paride Legovini (paride)]

It hit a timeout on vmtests.test_basic.FocalTestScsiBasic on s390x :(

https://paste.ubuntu.com/p/kDGGx4qsVv/

Retriggering.

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:101acb8c274c2de0e4f0a6758aa38bcc4813dca7

No commit message was specified in the merge proposal. Click on the following link and set the commit message (if you want jenkins to rebuild you need to trigger it yourself):
https://code.launchpad.net/~paride/curtin/+git/curtin/+merge/402652/+edit-commit-message

https://jenkins.ubuntu.com/server/job/curtin-ci/124/
Executed test runs:
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-amd64/124/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-arm64/124/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-ppc64el/124/
    FAILURE: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-s390x/124/

Click here to trigger a rebuild:
https://jenkins.ubuntu.com/server/job/curtin-ci/124//rebuild

review: Needs Fixing (continuous-integration)

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:101acb8c274c2de0e4f0a6758aa38bcc4813dca7

No commit message was specified in the merge proposal. Click on the following link and set the commit message (if you want jenkins to rebuild you need to trigger it yourself):
https://code.launchpad.net/~paride/curtin/+git/curtin/+merge/402652/+edit-commit-message

https://jenkins.ubuntu.com/server/job/curtin-ci/125/
Executed test runs:
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-amd64/125/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-arm64/125/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-ppc64el/125/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-s390x/125/

Click here to trigger a rebuild:
https://jenkins.ubuntu.com/server/job/curtin-ci/125//rebuild

review: Needs Fixing (continuous-integration)

[Server Team CI bot (server-team-bot)]

review: Approve (continuous-integration)

diff --git a/pylintrc b/pylintrc
index 67a4e01..1b5fa1a 100644
--- a/pylintrc
+++ b/pylintrc
@@ -7,7 +7,7 @@ jobs=0
 # List of members which are set dynamically and missed by pylint inference
 # system, and so shouldn't trigger E1101 when accessed. Python regular
 # expressions are accepted.
-generated-members=DISTROS\.
+generated-members=redhat,centos,fedora,debian,suse,opensuse,sles,arch,ubuntu,rhel,freebsd,gentoo
 
 # List of module names for which member attributes should not be checked
 # (useful for modules/projects where namespaces are manipulated during runtime