Remove https package from OPCFoundation.NetStandard.Opc.Ua dependencies, causes build issues.

Proposed changes

Multiple isses were reported when the OPCFoundation.NetStandard.Opc.Ua package is used with netstandard2.0 or unity, likely caused by dependencies in the https kestrel package. Make the https package optional (user needs to add it to the list of dependencies).

Package is also marked deprecated on Nuget.org.

Related Issues

Fixes #2741
Fixes #2722

Types of changes

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[x] Bugfix (non-breaking change which fixes an issue)
[ ] Enhancement (non-breaking change which adds functionality)
[ ] Test enhancement (non-breaking change to increase test coverage)
[ ] Breaking change (fix or feature that would cause existing functionality to not work as expected, requires version increase of Nuget packages)
[ ] Documentation Update (if none of the other choices apply)

Checklist

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[ ] I have read the CONTRIBUTING doc.
[ ] I have signed the CLA.
[ ] I ran tests locally with my changes, all passed.
[ ] I fixed all failing tests in the CI pipelines.
[ ] I fixed all introduced issues with CodeQL and LGTM.
[ ] I have added tests that prove my fix is effective or that my feature works and increased code coverage.
[ ] I have added necessary documentation (if appropriate).
[ ] Any dependent changes have been merged and published in downstream modules.

Further comments

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OPCFoundation / UA-.NETStandard