add pg13 on CI

.circleci/config.yml

@@ -45,6 +45,20 @@ jobs:
           paths:
             - install-12.tar
 
+  build-13:
+    docker:
+      - image: 'citus/extbuilder:13.0'
+    steps:
+      - checkout
+      - run:
+          name: 'Configure, Build, and Install'
+          command: |
+            PG_MAJOR=13 .circleci/build.sh
+      - persist_to_workspace:
+          root: .
+          paths:
+            - install-13.tar
+
   test-11_checkinstall:
     docker:
       - image: 'citus/exttester:11.9'
@@ -85,6 +99,26 @@ jobs:
       - codecov/upload:
           flags: 'test_12,installcheck'
 
+  test-13_checkinstall:
+    docker:
+      - image: 'citus/exttester:13.0'
+    working_directory: /home/circleci/project
+    steps:
+      - checkout
+      - attach_workspace:
+          at: .
+      - run:
+          name: 'Prepare Container & Install Extension'
+          command: |
+            chown -R circleci:circleci /home/circleci
+            tar xfv "${CIRCLE_WORKING_DIRECTORY}/install-${PG_MAJOR}.tar" --directory /
+      - run:
+          name: 'Run Test'
+          command: |
+            gosu circleci .circleci/run_test.sh installcheck
+      - codecov/upload:
+          flags: 'test_13,installcheck'
+
 workflows:
   version: 2
   build_and_test:
@@ -94,8 +128,11 @@ workflows:
 
       - build-11
       - build-12
+      - build-13
 
       - test-11_checkinstall:
           requires: [build-11]
       - test-12_checkinstall:
           requires: [build-12]
+      - test-13_checkinstall:
+          requires: [build-13]