[templates/angular] [templates/angular-sxp] [templates/angular-xmcloud] Updates for Angular XMC sample to work well with local containers and spa-starters monorepo in xmcloud-foundation

[yavorsk]

• This PR follows the Contribution Guide
• Changelog updated
• Upgrade guide entry added

Description / Motivation

The updates in this PR are done to support local containers with angular spa sample as rendering host:

• move style reference to bootstrap from angular base to angular-sxp template;
• update tsconfig to make angular spa app work well with spa-starters monorepo and local containers in xmcloud-foundation;
• use fs functions to delete and copy dist folder in proxy-build script;

Testing Details

• Unit Test Added
• Manual Test/Other (Please elaborate) - smoke test

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)