Update failIfCoverageEmpty to use default value to prevent the pipeline from failing

[LeafShi1]

Set the failIfCoverageEmpty property in build.yml and build-PR.yml to the default value to prevent the pipeline from failing due to release code coverage failure

Currently we are getting error in CI in Initialize job:

Starting: PublishCodeCoverageResults
==============================================================================
Task         : Publish code coverage results v2
Description  : Publish any of the code coverage results from a build
Version      : 2.252.1
Author       : Microsoft Corporation
Help         : https://docs.microsoft.com/azure/devops/pipelines/tasks/test/publish-code-coverage-results
==============================================================================
Found 0 result(s) matching pattern: D:\a\_work\1\s\artifacts\bin\CodeCoverage\coverage\full\Cobertura.xml
##[error]No code coverage results were found to publish.