fix: Hive integration

[budde377]

This PR fixes #1091. The underlying issue is that Hive doesn't work well with generics. By not assuming that the box will be Box<Map<String, dynamic>?>, but rather Box<Map<dynamic, dynamic>?> and handling conversion appropriately, we can prevent the bugs reported.

[codecov]

Codecov Report

Merging #1093 (a8726cb) into main (ebc96e7) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main    #1093   +/-   ##
=======================================
  Coverage   60.01%   60.01%           
=======================================
  Files          41       41           
  Lines        1528     1528           
=======================================
  Hits          917      917           
  Misses        611      611           

Impacted Files	Coverage Δ
packages/graphql/lib/src/cache/hive_store.dart	94.73% <100.00%> (ø)
packages/graphql/lib/src/cache/store.dart	100.00% <100.00%> (ø)

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[vincenzopalazzo]

just a minor in the commit message

the change required only the client changelog to be updated, so we need to use fix(graphql): ..