[PORT] [Expression] make indexOf/lastIndexOf function support list

[tomlm]

Port this change from botbuilder-dotnet/master branch:
microsoft/botbuilder-dotnet#3444

Orignially, indexOf and lastIndexOf just support string implement, for example:

indexOf('abc', 'b') => 2
indexOf('abc', 'd') => -1
lastIndexOf('abcab', 'ab') => 3

Current, the first parameter support list data type. So, the expression below is valid

indexOf(createArray('abc', 'def', 'ghi'), 'def')  => 1
indexOf(json('[\"a\", \"b\"]'), 'a') => 0
lastIndexOf(json('[\"a\", \"b\", \"a\"]'), 'a') => 2
lastIndexOf(createArray('abc', 'def', 'ghi', 'def'), 'def') => 3

Changed projects

• AdaptiveExpressions
• AdaptiveExpressions.Tests