Work around bug in git-parameter plugin

Git-parameter doesn't seem to work correctly with ssh urls, so use a
text parameter instead.

Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
Change-Id: Ia5e66d98c08156b47f6a2abfea8fffc373db48bb
diff --git a/mbed-tls-restricted-pr-test-parametrized.yaml b/mbed-tls-restricted-pr-test-parametrized.yaml
index b3cee7e..60a48a8 100644
--- a/mbed-tls-restricted-pr-test-parametrized.yaml
+++ b/mbed-tls-restricted-pr-test-parametrized.yaml
@@ -104,12 +104,11 @@
         description: Import mbed TLS into mbed-os master and test mbed TLS tls-client
           example.
         name: TEST_MBED_OS_TLS_CLIENT_EXAMPLE
-    - git-parameter:
+    - string:
         name: TEST_BRANCH
         description: Branch or tag in https://github.com/Mbed-TLS/mbedtls-test.git (forks are not supported)
-        type: PT_BRANCH_TAG
-        quickFilterEnabled: True
-        defaultValue: main
+        default: main
+        trim: 'false'
     pipeline-scm:
       lightweight-checkout: false
       scm: