[REFACTOR] Refactor Builders to avoid need for instantiation

[dbwiddis]

Is your feature request related to a problem?

Instantiating a builder shouldn't require so much new in the code.

What solution would you like?

Change builder instantiation from the current new Template.Builder() to static method Template.builder(). (Use multiple methods for the ones with arguments.)

These can be easily replaced in code via regex search/replace.

Can do similar for the Workflow State builder, probably at the same time as #713

Do you have any additional context?

Sample PR for what I want to do:

• [Feature/multi_tenancy] Simplify instantiating Data Object Request/Response builders ml-commons#2608