fix(syntax): correct parentheses around union (#9813)

[tsasaki609]

Pull Request check-list

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Description of change

fix #9813

I wrapped a subquery to union.
Although it is a little tricky, no error occurs with this.

[codecov]

Codecov Report

Merging #10003 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master   #10003   +/-   ##
=======================================
  Coverage   96.38%   96.38%           
=======================================
  Files          63       63           
  Lines        9382     9382           
=======================================
  Hits         9043     9043           
  Misses        339      339

Impacted Files	Coverage Δ
lib/dialects/abstract/query-generator.js	97.65% <100%> (ø)	⬆️

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[tsasaki609]

How is it like this?

[sushantdhiman]

Thanks @tsasaki609

Not sure when you last pushed the change, I didn't get any notification for last commit

[internalfx]

Is this in the latest release yet? I'm still seeing this bug.

[sushantdhiman]

@internalfx 5.0.0-beta.13

[internalfx]

Any chance for a 4.x branch release?

[sushantdhiman]

@internalfx cherry pick this commit and send a PR targeting v4 branch

[tzellman]

Thanks @sushantdhiman! PR #10121 targets the v4 branch.