refactor(storage): remove source when there is a from attribute

[lmatz]

What's changed and what's your intention?

The #[from] attribute always implies that the same field is #[source], so you don't ever need to specify both attributes.

Checklist

- [ ] I have written necessary docs and comments
- [ ] I have added necessary unit tests and integration tests

• All checks passed in ./risedev check (or alias, ./risedev c)

Refer to a related PR or issue link (optional)

[codecov]

Codecov Report

Merging #3267 (ca0c123) into main (c824303) will decrease coverage by 0.00%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #3267      +/-   ##
==========================================
- Coverage   73.22%   73.22%   -0.01%     
==========================================
  Files         747      747              
  Lines      101892   101892              
==========================================
- Hits        74614    74613       -1     
- Misses      27278    27279       +1     

Flag	Coverage Δ
rust	73.22% <ø> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
src/object_store/src/object/error.rs	33.33% <ø> (ø)
src/storage/src/error.rs	0.00% <ø> (ø)
src/meta/src/barrier/mod.rs	69.94% <0.00%> (-0.30%)	⬇️

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