refactor(support): remove support for 2020.3 and add support for 2022.2

the `CallingSmartContractAbi` sample does not support 2020.3 as it relies on UI Elements

BREAKING CHANGE: Unity 2020.3 is no longer supported

README.md

@@ -52,12 +52,12 @@ This package supports the following build targets and Unity versions:
 
 | Unity Version |      Windows       |       Mac OS       |       Linux        |      Android       |        iOS         |           WebGL            |
 | :-----------: | :----------------: | :----------------: | :----------------: | :----------------: | :----------------: | :------------------------: |
-|    2020.3     | :white_check_mark: |        :x:         | :white_check_mark: | :white_check_mark: | :white_check_mark: | :eight_pointed_black_star: |
+|    2020.3     |        :x:         |        :x:         |        :x:         |        :x:         |        :x:         |            :x:             |
 |    2021.3     | :white_check_mark: | :white_check_mark: | :white_check_mark: | :white_check_mark: | :white_check_mark: | :eight_pointed_black_star: |
-|    2022.1     | :white_check_mark: | :white_check_mark: | :white_check_mark: | :white_check_mark: | :white_check_mark: | :eight_pointed_black_star: |
+|    2022.2     | :white_check_mark: | :white_check_mark: | :white_check_mark: | :white_check_mark: | :white_check_mark: | :eight_pointed_black_star: |
 
 - :white_check_mark: All APIs are supported.
-- :eight_pointed_black_star: `Algorand.*.*Api` clients are not supported.
+- :eight_pointed_black_star: `Algorand.Unity.Net` is not supported. This assembly is used to enable cross-compatibility between the .NET SDK and the Unity SDK.
 - :x: Not supported. Use at your own risk.
 
 ## Common Usages