DRIVERS-1709: Convert legacy transactions spec tests to unified test format (#1502)

* Move legacy test format docs to separate file

* Batch convert legacy spec files

* Consolidate $$unsetOrMatches, $$type, $$exists, $$sessionLsid, and $numberLong

* Consolidate document objects and configureFailPoint times option

* Consolidate forbid_serverless using test-level runOnRequirements

These files were originally split off in DRIVERS-2713 since the legacy format only allowed top-level requirements.

* Use int|long for all getMore cursor ID type checking

* Use lowercase read preference mode strings

* DRIVERS-2834: Prohibit LB topology for tests using targetedFailPoint

Adds clarification to the unified test format spec.

Author: jmikola

source/client-side-encryption/tests/README.rst

@@ -39,7 +39,7 @@ are true:
 Spec Test Format
 ================
 
-The spec tests format is an extension of `transactions spec tests <https://github.com/mongodb/specifications/blob/master/source/transactions/tests/README.rst>`_ with some additions:
+The spec tests format is an extension of the `transactions spec legacy test format <https://github.com/mongodb/specifications/blob/master/source/transactions/tests/legacy-test-format.rst>`__ with some additions:
 
 - A ``json_schema`` to set on the collection used for operations.
 

source/read-write-concern/tests/README.rst

@@ -57,7 +57,7 @@ Operation
 
 These tests check that the default write concern is omitted in operations.
 
-The spec test format is an extension of `transactions spec tests <https://github.com/mongodb/specifications/blob/master/source/transactions/tests/README.rst>`_ with the following additions:
+The spec test format is an extension of the `transactions spec legacy test format <https://github.com/mongodb/specifications/blob/master/source/transactions/tests/legacy-test-format.rst>`__ with the following additions:
 
 - ``writeConcern`` in the ``databaseOptions`` or ``collectionOptions`` may be an empty document to indicate a `server default write concern <https://github.com/mongodb/specifications/blob/master/source/read-write-concern/read-write-concern.rst#servers-default-writeconcern>`_. For example, in libmongoc: