Parallel Include Improvements

[reid-spencer]

Fixes some time-out issues because of using Java's Executor not Scala's ExecutionContext.
Also made it avoid using Futures/parallelism at all if maxParallelParsing is < 2

[github-actions]

Pull Request Test Coverage Report for Build 7702962103

• -2 of 19 (89.47%) changed or added relevant lines in 3 files are covered.
• 43 unchanged lines in 20 files lost coverage.
• Overall coverage decreased (-0.003%) to 60.481%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
language/src/main/scala/com/ossuminc/riddl/language/parsing/ParsingContext.scala	14	16	87.5%

Files with Coverage Reduction	New Missed Lines	%
language/src/main/scala/com/ossuminc/riddl/language/Messages.scala	1	85.25%
language/src/main/scala/com/ossuminc/riddl/language/parsing/EntityParser.scala	1	72.73%
language/src/main/scala/com/ossuminc/riddl/language/parsing/EpicParser.scala	1	39.33%
language/src/main/scala/com/ossuminc/riddl/language/parsing/FunctionParser.scala	1	69.57%
language/src/main/scala/com/ossuminc/riddl/language/parsing/HandlerParser.scala	1	39.29%
language/src/main/scala/com/ossuminc/riddl/language/parsing/Keywords.scala	1	48.45%
language/src/main/scala/com/ossuminc/riddl/language/parsing/ParsingContext.scala	1	75.71%
language/src/main/scala/com/ossuminc/riddl/language/parsing/ProjectorParser.scala	1	57.14%
language/src/main/scala/com/ossuminc/riddl/language/parsing/Readability.scala	1	73.91%
language/src/main/scala/com/ossuminc/riddl/language/parsing/TopLevelParser.scala	1	83.78%

Totals
Change from base Build 7687891431:	-0.003%
Covered Lines:	4452
Relevant Lines:	7361

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💛 - Coveralls