gh-155319: Fix the source line of a warning issued with module_globals

[serhiy-storchaka]

call_show_warning() passed None in the line slot of WarningMessage, so the source line computed from module_globals was discarded.

get_source_line() also raised IndexError if lineno was out of the range of the module source. It was not visible before, because the result was not used.

The pure Python implementation, which seeds linecache, was not affected.

• Issue: warn_explicit() discards the source line obtained from module_globals #155319

[miss-islington-app]

Thanks @serhiy-storchaka for the PR 🌮🎉.. I'm working now to backport this PR to: 3.13, 3.14, 3.15.
🐍🍒⛏🤖

[miss-islington-app]

Sorry, @serhiy-storchaka, I could not cleanly backport this to 3.14 due to a conflict.
Please backport using cherry_picker on command line.

cherry_picker c92e2fd8f9c8af3ea383dec6222cfcca47a405ff 3.14

[bedevere-app]

GH-155824 is a backport of this pull request to the 3.15 branch.

[miss-islington-app]

Sorry, @serhiy-storchaka, I could not cleanly backport this to 3.13 due to a conflict.
Please backport using cherry_picker on command line.

cherry_picker c92e2fd8f9c8af3ea383dec6222cfcca47a405ff 3.13

[bedevere-app]

GH-155825 is a backport of this pull request to the 3.14 branch.

[bedevere-app]

GH-155826 is a backport of this pull request to the 3.13 branch.

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot ARM64 Windows Non-Debug 3.13 (tier-2) has failed when building commit f61481f.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/2006/builds/272) and take a look at the build logs.
4. Check if the failure is related to this commit (f61481f) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/2006/builds/272

Failed tests:

• test_int

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last):
  File "C:\Users\buildworker\buildarea\3.13.ware-win11-arm64.nondebug\build\Lib\test\test_int.py", line 740, in test_denial_of_service_prevented_str_to_int
    self.assertLessEqual(sw_fail_extra_huge.seconds, sw_convert.seconds/2)
    ~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AssertionError: 0.015625 not less than or equal to 0.0078125