Upgrade OPM to 1.20.0

  - Upgrade OPM to 1.20.0 in Dockerfile-workers
  - Replace `opm alpha generate` with `opm generate`

Refers to CLOUDDST-11845

docker/Dockerfile-workers

@@ -24,7 +24,7 @@ RUN dnf -y install \
     && dnf update -y \
     && dnf clean all
 
-ADD https://github.com/operator-framework/operator-registry/releases/download/v1.19.5/linux-amd64-opm /usr/bin/opm
+ADD https://github.com/operator-framework/operator-registry/releases/download/v1.20.0/linux-amd64-opm /usr/bin/opm
 RUN chmod +x /usr/bin/opm
 ADD https://github.com/fullstorydev/grpcurl/releases/download/v1.8.5/grpcurl_1.8.5_linux_x86_64.tar.gz /src/grpcurl_1.8.5_linux_x86_64.tar.gz
 RUN cd /usr/bin && tar -xf /src/grpcurl_1.8.5_linux_x86_64.tar.gz grpcurl && rm -f /src/grpcurl_1.8.5_linux_x86_64.tar.gz

iib/workers/tasks/opm_operations.py

@@ -354,7 +354,6 @@ def opm_generate_dockerfile(fbc_dir, base_dir, index_db, binary_image, dockerfil
 
     cmd = [
         'opm',
-        'alpha',
         'generate',
         'dockerfile',
         os.path.abspath(fbc_dir),

tests/test_workers/test_tasks/test_opm_operations.py

@@ -197,7 +197,7 @@ def create_dockerfile(*args, **kwargs):
     df_name = dockerfile if dockerfile else f"{os.path.basename(fbc_dir)}.Dockerfile"
 
     mock_run_cmd.assert_called_once_with(
-        ['opm', 'alpha', 'generate', 'dockerfile', fbc_dir, '--binary-image', 'some:image'],
+        ['opm', 'generate', 'dockerfile', fbc_dir, '--binary-image', 'some:image'],
         {'cwd': tmpdir},
         exc_msg='Failed to generate Dockerfile for file-based catalog',
     )
@@ -223,7 +223,7 @@ def test_opm_generate_dockerfile_no_dockerfile(mock_run_cmd, tmpdir, set_index_d
         )
 
     mock_run_cmd.assert_called_once_with(
-        ['opm', 'alpha', 'generate', 'dockerfile', fbc_dir, '--binary-image', 'some:image'],
+        ['opm', 'generate', 'dockerfile', fbc_dir, '--binary-image', 'some:image'],
         {'cwd': tmpdir},
         exc_msg='Failed to generate Dockerfile for file-based catalog',
     )