[Shipa-2871] Adds volume name validators

[kavinaravind]

Description

This PR focuses on extra validation checks for volumes

1. A compliant k8 volume name (conforms to the following regex: "[a-z0-9]([-a-z0-9]*[a-z0-9])?")
2. Explicitly checking that the pvc exists via a k8 call and erroring if it does not

Fixes # (issue)

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Chore (documentation addition or typo, file relocation)

Testing

• New tests were added with this PR that prove my fix is effective or that my feature works (describe below this bullet)
• This change requires no testing (i.e. documentation update)

Documentation

• All added public packages, funcs, and types have been documented with doc comments
• I have commented my code, particularly in hard-to-understand areas

Final Checklist:

• I followed standard GitHub flow guidelines
• I have performed a self-review of my own code
• My changes generate no new warnings

Additional Information (omit if empty)

Please include anything else relevant to this PR that may be useful to know.