Updated MSALAuthenticationProvider's constructor to accept an instance of UserAgentApplication

[muthurathinam]

Summary

Updated MSALProvider's constructor to accept UserAgentApplication

Motivation

Accepting UserAgentApplication reduces the implementing interfaces for functionalities of userAgentApplication inside provider.

Test plan

• Initialize the UserAgentApplication and Pass in the instance while initializing the MSALAuthenticationProvider.
• Browser Sample also updated with same as above so running the browser sample will also ensure its validation.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

[NakulSabharwal]

Looks fine.