doc: use YAML list format for fullName version metadata

- Updated both TestContext#fullName and SuiteContext#fullName
- Changed from single version to YAML list format with both v22.3.0 and v20.16.0
- Reflects that fullName was added in v22.3.0 and backported to v20.16.0

Author: PaulyBearCoding

doc/api/test.md

@@ -3667,7 +3667,9 @@ the path of the root test file.
 ### `context.fullName`
 
 <!-- YAML
-added: v20.16.0
+added:
+  - v22.3.0
+  - v20.16.0
 -->
 
 The name of the test and each of its ancestors, separated by `>`.
@@ -3973,7 +3975,9 @@ return the path of the root test file.
 ### `context.fullName`
 
 <!-- YAML
-added: v20.16.0
+added:
+  - v22.3.0
+  - v20.16.0
 -->
 
 The name of the suite and each of its ancestors, separated by `>`.