[TASK] Remove functional testing with postgres and sqlite db

Postgres and Sqlite will not be supported by the extension for the moment.
FROM_UNIXTIME can not be used. Code must be changed before running/testing
operations with those db systems.

.github/workflows/ci.yml

@@ -29,9 +29,3 @@ jobs:
 
       - name: Functional tests with mariadb
         run: Build/Scripts/runTests.sh -p ${{ matrix.php }} -d mariadb -s functional
-
-      - name: Functional tests with postgres
-        run: Build/Scripts/runTests.sh -p ${{ matrix.php }} -d postgres -s functional
-
-      - name: Functional tests with sqlite
-        run: Build/Scripts/runTests.sh -p ${{ matrix.php }} -d sqlite -s functional