* [DOCS] Adding get snapshot API docs (#59098)
* Adding page for get snapshot API.
* Adding values for state and cleaning up some other formatting.
* Adding missing forward slash to GET request.
* Updating values for start_time and end_time in TESTRESPONSE.
* Swap "return" for "retrieve"
* Swap "return" for "retrieve" 2
* Change .snapshot to .response
* Adding response parameters and incorporating edits from review.
* Update response example to include repository info
* Change dash to underscore
* Add data type for snapshot in response
* Incorporating review comments and adding missing response definitions.
* Minor rewording in description.
* Removing multi-snapshot support for 7.x.
* Changing end_time value from build error.
* Removing .response from snippet testing.
* Adding create index snapshot API page.
* Condense API description.
* Remove parameter from query.
* Add POST method and remove `-name` from the snapshot variable.
* Expand description of `<snapshot>`.
* Add data streams to introduction and expand the overall description.
* Add support for data streams.
* Add support for data streams.
* Add data stream and reference for "point-in-time view".
* Add data streams.
* Change `my_backup` to `my_repository`.
* Add description of boolean options for `wait_for_completion` parameter.
* Change command --> response
* Clarify `indices` parameter description
* Update `ignore-unavailable` parameter description
* Reword example description
* Remove "index" from API name
* Incorporating review comments from James R.
* Adding a much better request + response
* Clarify `include_global_state` description
* Incorporating additional edits.
* Changing my_backup to my_repository in example.
* Update snippet test to avoid failures
* Update TESTRESPONSE snippets
* Remove errant space
* Removing the parameter per reviewer comments
Changes:
* Adds API reference docs for the delete snapshot repo API.
* Corrects an error in the delete snapshot repo API spec. Comma-separated
repository names are not supported.
* Relocates the existing delete snapshot repo API example docs.
Adam Locke
James Rodewig