Manage index settings in Vespa application package

[papa99do]

• What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)
  Reliability improvements

• What is the current behavior? (You can also link to an open issue here)

• Index settings are maintained in a Vespa schema, which has consistency issue
• Marqo config is stored as a document in Vespa
• Vespa Bootstrapping is done once-off

• What is the new behavior (if this is a feature change)?

• Index settings are maintained within the Vespa application package
• Marqo config is stored within the Vespa application package
• Bootstrapping of the Vespa app is done automatcially on every Marqo release
• Provided a way to safely rollback to the previous version of Marqo

• Does this PR introduce a breaking change? (What changes might users need to make in their application due to this PR?)
  No, there are no changes to the external APIs or customer-facing behaviour of Marqo

• Have unit tests been run against this PR? (Has there also been any additional testing?)
  Yes

• Related Python client changes (link commit/PR here)
  N/A

• Related documentation changes (link commit/PR here)
  N/A

• Other information:

• Please check if the PR fulfills these requirements

• The commit message follows our guidelines
• Tests for the changes have been added (for bug fixes/features)
• Docs have been added / updated (for bug fixes / features)