[#6558] Update to ANTLR 4.11 to compensate for breaking changes between versions

[sw-joelmut]

Fixes #6558

Note: This PR was based on the changes made in the pull request #6557.

Description

This PR upgrades the ANTLR from 4.8.0 to 4.11.1 in the AdaptiveExpressions and LanguageGeneration libraries.

Specific Changes

• Updates ANTLR dependency version from 4.8.0 to 4.11.1 in AdaptiveExpressions.csproj, Microsoft.Bot.Builder.LanguageGeneration.csproj and AdaptiveExpressions.Tests.csproj.
• Updates the README.md files with the new commands to generate the files.
• Updates all the files under the Generated folder with the commands listed in the README.md executing ANTLR.
• Updates some .g4 files due to having a problem with the BOM encoding and EOF character.

Testing

The following image shows the build and test passing successfully with the applied changes.

[coveralls]

Pull Request Test Coverage Report for Build 340146

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 262 unchanged lines in 8 files lost coverage.
• Overall coverage increased (+0.02%) to 73.373%

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Files with Coverage Reduction	New Missed Lines	%
/libraries/Microsoft.Bot.Builder.LanguageGeneration/Generated/LGFileParserBaseVisitor.cs	7	30.0%
/libraries/AdaptiveExpressions/Generated/ExpressionAntlrParserBaseVisitor.cs	21	4.55%
/libraries/Microsoft.Bot.Builder.LanguageGeneration/Generated/LGTemplateParserBaseVisitor.cs	23	8.0%
/libraries/Microsoft.Bot.Builder.LanguageGeneration/Generated/LGFileParserBaseListener.cs	24	0%
/libraries/AdaptiveExpressions/Generated/CommonRegexBaseVisitor.cs	27	0%
/libraries/AdaptiveExpressions/Generated/ExpressionAntlrParserBaseListener.cs	48	0%
/libraries/Microsoft.Bot.Builder.LanguageGeneration/Generated/LGTemplateParserBaseListener.cs	54	0%
/libraries/AdaptiveExpressions/Generated/CommonRegexBaseListener.cs	58	0%

Totals
Change from base Build 337253:	0.02%
Covered Lines:	23952
Relevant Lines:	32644

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💛 - Coveralls