Fixes Regex to match only container files more strictly

[Chocrates]

Fixes #4846

Proposed Changes

We check for files with the name (case insensitive):

• Dockerfile
• Containerfile
• .Dockerfile
• .Containerfile

This appears to protect us against catching files with a name like Dockerfile.md

I tested the regex like so:

Readiness Checklist

Author/Contributor

• If documentation is needed for this change, has that been included in this pull request

Reviewing Maintainer

• Label as breaking if this is a large fundamental change
• Label as either automation, bug, documentation, enhancement, infrastructure, or performance

[zkoppert]

Great! Thank you! Appreciate the testing!

[Chocrates]

I haven't run an end to end test on this sha yet, I need to read up on running it locally. Do you know what the testing errors are about? I haven't dug in to them deeply but looks like it was expecting ansible tests that weren't found?

https://github.com/super-linter/super-linter/actions/runs/6856308690/job/18644478272?pr=4867#step:9:1936

[zkoppert]

I'll take a look. 👀

[zkoppert]

This may be the actual problem: https://github.com/super-linter/super-linter/actions/runs/6857323015/job/18646199332?pr=4867#step:9:17

[ferrarimarco]

I think there's an extra space before the regex. :)

[ferrarimarco]

Also, I wonder if we can add some test cases for this regex...

[zkoppert]

Think we got this one dialed in now.