Refactor OPA tests (cvat-ai#5373)

- OPA tests are now autogenerated
- Updated invocation docs

Author: zhiltsov-max

.github/workflows/full.yml

@@ -243,6 +243,9 @@ jobs:
 
       - name: Running OPA tests
         run: |
+          python cvat/apps/iam/rules/tests/generate_tests.py \
+            --output-dir cvat/apps/iam/rules/
+
           curl -L -o opa https://openpolicyagent.org/downloads/v0.34.2/opa_linux_amd64_static
           chmod +x ./opa
           ./opa test cvat/apps/iam/rules

.github/workflows/main.yml

@@ -209,6 +209,9 @@ jobs:
 
       - name: Running OPA tests
         run: |
+          python cvat/apps/iam/rules/tests/generate_tests.py \
+            --output-dir cvat/apps/iam/rules/
+
           curl -L -o opa https://openpolicyagent.org/downloads/v0.34.2/opa_linux_amd64_static
           chmod +x ./opa
           ./opa test cvat/apps/iam/rules