fix: when transactions enabled throw errors when needed

[cbaker6]

New Pull Request Checklist

• I am not disclosing a vulnerability.
• I am creating this PR in reference to an issue.

Issue Description

When using transactions, issues can arise when:

1. The number of objects in the transaction are larger than the batch size
2. When child objects haven't been saved

Currently the SDK:

1. Adjusts the batch size to the size of the objects in the transaction. This can be problematic when the number is large
2. Saves unsaved children as individual transactions. If parents can't save after, the original transaction can't be cancelled

Related issue: #n/a

Approach

Implement the suggestions in parse-community/Parse-SDK-JS#1090 (comment)

TODOs before merging

• Add tests
• Add changes to documentation (guides, repository pages, in-code descriptions)

[parse-github-assistant]

Thanks for opening this pull request!

• 🎉 We are excited about your hands-on contribution!

[codecov]

Codecov Report

Merging #295 (7c26b73) into main (1352a83) will increase coverage by 0.08%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #295      +/-   ##
==========================================
+ Coverage   82.70%   82.79%   +0.08%     
==========================================
  Files         104      104              
  Lines       10638    10622      -16     
==========================================
- Hits         8798     8794       -4     
+ Misses       1840     1828      -12     

Impacted Files	Coverage Δ
...s/ParseSwift/Objects/ParseInstallation+async.swift	100.00% <ø> (ø)
...ParseSwift/Objects/ParseInstallation+combine.swift	100.00% <ø> (ø)
Sources/ParseSwift/Objects/ParseObject+async.swift	100.00% <ø> (ø)
...urces/ParseSwift/Objects/ParseObject+combine.swift	100.00% <ø> (ø)
Sources/ParseSwift/Objects/ParseUser+async.swift	100.00% <ø> (ø)
Sources/ParseSwift/Objects/ParseUser+combine.swift	100.00% <ø> (ø)
Sources/ParseSwift/Objects/ParseInstallation.swift	77.29% <100.00%> (-0.43%)	⬇️
Sources/ParseSwift/Objects/ParseObject.swift	79.12% <100.00%> (+3.00%)	⬆️
Sources/ParseSwift/Objects/ParseUser.swift	79.51% <100.00%> (-0.47%)	⬇️
Sources/ParseSwift/Parse.swift	98.75% <100.00%> (ø)
... and 2 more

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[RahulLanjewar93]

@cbaker6 Hi, just wanted to know what are we doing exactly here to solve both issues.
I'll try to do the same in Parse-JS-SDK