Remove full provider's specification from TEST_TYPES (apache#24901)

The new provider's selective tests introduce option to specify
which providers should be tested (which is automatically
used in CI). This works fine but in case when we remove
Provider's tests from the list (MySQL/MsSQL) the removal was
done only for the Provider's part, not for the detailed list
of providers. That led to test attempting to run
```
[amazon,apache.hive,google,mysql,postgres]
```

for example.

This PR fixes it by removing full Provider's specification.

Author: potiuk

scripts/ci/testing/ci_run_airflow_testing.sh

@@ -107,7 +107,8 @@ function run_all_test_types_in_parallel() {
             # Those tests will run in `main` anyway.
             if [[ ${test_types_to_run} == *"Providers"* ]]; then
                 echo "${COLOR_YELLOW}Remove Providers from tests_types_to_run and skip running them altogether (mysql/mssql case).${COLOR_RESET}"
-                test_types_to_run="${test_types_to_run//Providers/}"
+                # shellcheck disable=SC2001
+                test_types_to_run=$(echo "${test_types_to_run}" | sed 's/Providers[^ ]* *//')
             fi
         fi
     fi