fix: typo for the builder error type

[JosephLenton]

Which issue does this PR close?

There is no ticket for this (I can open one if it is really needed). This is a very small nitpick QoL improvement, by changing the wording for an error.

The typo fixes the phrase ... can't cast to got ..., by adding a comma and making the rest a bit clearer.

Rationale for this change

• The error doesn't read as natural english with ... can't cast to got ....
• I've added more clarity on what got and for are, by changing to data of type and field of type.

What changes are included in this PR?

• Rewording an error message.

Are these changes tested?

• I added a test to confirm the error message looks right.

Are there any user-facing changes?

• A user facing error message has changed.
• No documentation changes are needed.
• No API breaking changes are in this PR.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80.85%. Comparing base (541caab) to head (5a0c76f).
⚠️ Report is 25 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #24052      +/-   ##
==========================================
+ Coverage   80.84%   80.85%   +0.01%     
==========================================
  Files        1096     1101       +5     
  Lines      373936   375446    +1510     
  Branches   373936   375446    +1510     
==========================================
+ Hits       302313   303582    +1269     
- Misses      53584    53768     +184     
- Partials    18039    18096      +57     

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