feat(storage): Add check for writeHandle before reansforming write_object_spec to append_object_spec

[v-pratap]

This change will only allow transformation from write_obejct_spec to append_object_spec when error has write handle, because the failure without write handle needs write_object_spec as input for retry.

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This change is 

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 92.94%. Comparing base (a2dc298) to head (b1a89d1).
Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #15224      +/-   ##
==========================================
- Coverage   92.94%   92.94%   -0.01%     
==========================================
  Files        2394     2394              
  Lines      215552   215592      +40     
==========================================
+ Hits       200345   200382      +37     
- Misses      15207    15210       +3     

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[scotthart]

Reviewable status: 0 of 5 files reviewed, all discussions resolved (waiting on @ddelgrosso1)

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google/cloud/storage/internal/async/handle_redirect_error.cc line 28 at r3 (raw file):

  for (auto const& rpc_status_detail : rpc_status.details()) {
    google::storage::v2::BidiWriteObjectRedirectedError error =
        google::storage::v2::BidiWriteObjectRedirectedError{};

google::storage::v2::BidiWriteObjectRedirectedError error;

Code quote:

    google::storage::v2::BidiWriteObjectRedirectedError error =
        google::storage::v2::BidiWriteObjectRedirectedError{};