fix: improve annotation extraction by trimming whitespace

[vdegans]

Type of change:

• Bugfix
• Refactor
• Chore

What this PR does / why we need it:

Fixes: #2723

Currently, annotations that accept comma-separated lists (such as whitelist-source-range and blacklist-source-range) are not trimmed, so any spaces after commas are preserved. This results in IP entries starting with a space, which breaks the whitelist and blacklist functionality.

This PR trims whitespace from each annotation item before processing, ensuring that spaces after commas do not cause parsing errors.

Behavior Before / After:

Aspect: Annotation parsing
Before: "1.2.3.4, 5.6.7.8" -> ["1.2.3.4", " 5.6.7.8"]
After: "1.2.3.4, 5.6.7.8" -> ["1.2.3.4", "5.6.7.8"]

Aspect: Whitelist/Blacklist enforcement
Before: Fails for entries with leading spaces
After: Works correctly for all entries

Related issues, if any:

• bug: Ingress annotations: comma-separated values are not trimmed, causing invalid IP parsing when spaces are present #2723

Pre-submission checklist:

• Did you explain what problem this PR solves? Or what new features have been added?
• Have you added corresponding test cases?
• Have you modified the corresponding document?
• Is this PR backward compatible? If it is not backward compatible, please discuss on the mailing list first

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