docs: fix releaseNoteLink for v2.8.0

[apricote]

Description

Fixes the link to the v2.8.0 changelog on https://skaffold.dev/docs/references/yaml/.

The current link leads to a 404. The actual tag has a v prefix.

User facing changes (remove if N/A)

Follow-up Work (remove if N/A)

[google-cla]

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[codecov]

Codecov Report

Merging #9125 (164afa0) into main (290280e) will decrease coverage by 7.05%.
Report is 1041 commits behind head on main.
The diff coverage is 48.33%.

@@            Coverage Diff             @@
##             main    #9125      +/-   ##
==========================================
- Coverage   70.48%   63.44%   -7.05%     
==========================================
  Files         515      628     +113     
  Lines       23150    32331    +9181     
==========================================
+ Hits        16317    20511    +4194     
- Misses       5776    10259    +4483     
- Partials     1057     1561     +504     

Files	Coverage Δ
cmd/skaffold/app/cmd/commands.go	97.61% <100.00%> (+0.35%)	⬆️
cmd/skaffold/app/cmd/config.go	100.00% <100.00%> (ø)
cmd/skaffold/app/cmd/config/list.go	65.21% <ø> (ø)
cmd/skaffold/app/cmd/config/set.go	88.72% <ø> (ø)
cmd/skaffold/app/cmd/config/util.go	54.28% <ø> (ø)
cmd/skaffold/app/cmd/credits.go	100.00% <ø> (ø)
cmd/skaffold/app/cmd/debug.go	100.00% <100.00%> (ø)
cmd/skaffold/app/cmd/flags.go	93.00% <100.00%> (+2.18%)	⬆️
cmd/skaffold/app/cmd/generate_pipeline.go	60.00% <ø> (ø)
cmd/skaffold/app/cmd/init.go	100.00% <100.00%> (ø)
... and 41 more

... and 431 files with indirect coverage changes

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