[Resources] Use JsonExtensions to serialize and deserialize template and parameter objects

[jorgecotillo]

Description

Checklist

• I have read the Submitting Changes section of CONTRIBUTING.md
• The title of the PR is clear and informative
• The appropriate ChangeLog.md file(s) has been updated:
  • For any service, the ChangeLog.md file can be found at src/{{SERVICE}}/{{SERVICE}}/ChangeLog.md
  • A snippet outlining the change(s) made in the PR should be written under the ## Upcoming Release header -- no new version header should be added
• The PR does not introduce breaking changes
• If applicable, the changes made in the PR have proper test coverage
• For public API changes to cmdlets:
  • a cmdlet design review was approved for the changes in this repository (Microsoft internal only)
    • {Please put the link here}
  • the markdown help files have been regenerated using the commands listed here

[jorgecotillo]

Added this reference to be able to access JsonExtensions, probably, as a future PR, consider moving JsonExtensions to a common project.

[Xynoclafe]

LGTM

[isra-fel]

LGTM

[jorgecotillo]

Just fixed a merge conflict in ChangeLog.md, do we have an ETA when this fix will be merged and after is merged how long it takes for it to be published? Thanks!

[isra-fel]

Next official release will be September 7

[ChristopherGLewis]

Did this break Tag case sensitivity?

#15876