chore: [#3518] Remove public access modifier from botbuilder-lg

[sw-joelmut]

Addresses #3518
#minor

Description

This PR removes the public access modifier from all constructors, methods and properties for the botbuilder-lg folder.

Note: These changes do not include the Typescript Constructor Shorthands (link).

Specific Changes

• Removes all public access modifiers from where it's declared under the botbuilder-lg folder.

[coveralls]

Pull Request Test Coverage Report for Build 2258454323

• 58 of 59 (98.31%) changed or added relevant lines in 8 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.003%) to 84.48%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
libraries/botbuilder-lg/src/analyzerOptions.ts	0	1	0.0%

Totals
Change from base Build 2245574340:	-0.003%
Covered Lines:	19902
Relevant Lines:	22310

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💛 - Coveralls