Improve GRADLE build Performance

[ChenZhangg]

Parallel test execution maxParallelForks. Gradle can run multiple test cases in parallel by setting maxParallelForks.

Disable report generation. We can conditionally disable it by setting reports.html.required = false; reports.junitXml.required = false. If you need to generate reports, add -PcreateReports to the end of Gradle's build command line.

Process forking options. Gradle will run all tests in a single forked VM by default. This can be problematic if there are a lot of tests or some very memory-hungry ones. We can fork a new test VM after a certain number of tests have run by setting forkEvery.

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If there are any inappropriate modifications in this PR, please give me a reply and I will change them.

[codecov-commenter]

Codecov Report

Merging #434 (3e7a24a) into series/5.x (2ee2950) will decrease coverage by 1.26%.
The diff coverage is n/a.

@@               Coverage Diff                @@
##             series/5.x     #434      +/-   ##
================================================
- Coverage         53.71%   52.44%   -1.27%     
+ Complexity         2624     2622       -2     
================================================
  Files               140      148       +8     
  Lines              9232     9444     +212     
  Branches            494      497       +3     
================================================
- Hits               4959     4953       -6     
- Misses             4118     4336     +218     
  Partials            155      155              

Impacted Files	Coverage Δ
core/src/main/java/fj/data/fingertrees/Single.java	81.48% <0.00%> (-3.71%)	⬇️
core/src/main/java/fj/Show.java	55.55% <0.00%> (-2.00%)	⬇️
core/src/main/java/fj/Equal.java	68.91% <0.00%> (-1.46%)	⬇️
core/src/main/java/fj/P.java	40.81% <0.00%> (-0.28%)	⬇️
core/src/main/java/fj/Hash.java	29.55% <0.00%> (-0.19%)	⬇️
core/src/main/java/fj/Semigroup.java	64.15% <0.00%> (-0.07%)	⬇️
core/src/main/java/fj/data/IO.java	0.00% <0.00%> (ø)
core/src/main/java/fj/function/Effect1.java	0.00% <0.00%> (ø)
core/src/main/java/fj/data/SafeIO.java	0.00% <0.00%> (ø)
core/src/main/java/fj/function/Try0.java	0.00% <0.00%> (ø)
... and 18 more

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