Fixed alignment source for Layout/RescueEnsureAlignment when using inline access modifiers

[andrew-aladev]

Closes #6326.

1. Fixed alignment source for autocorrect and check methods.
2. Implemented alignment node as a parent node + access modifier (if it exists).
3. I haven't added any fixed node types like :send. Code requires node only respond to access_modifier?. So it will be easy to add any other inline modifiers in future.
4. Cosmetics to fit with current project styles.

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• Commit message starts with [Fix #issue-number] (if the related issue exists).
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• Squashed related commits together.
• Added tests.
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[andrew-aladev]

Closes #6313.

[andrew-aladev]

Sorry, I was very busy this week. I will update it today.

[andrew-aladev]

I've removed merge commits and squashed it in single commit again. Ok? Done. Please review.

[iGEL]

Looks fine to me ❤️

[a14m]

Thanks a lot for the work, are we expecting this to soon be merged and released?
Thanks again for the awesome work 👍