Revert "Re-enable selection UI for TEST_BRANCH"

This reverts commit 514d5f79b8809c76635a3b4b030a03513fc4e82e.

Reason for revert: Bug in Git parameter plugin

Change-Id: I1535db76ded12a863d7373aaa6caf33c72bfa33e
diff --git a/mbed-tls-restricted-pr-test-parametrized.yaml b/mbed-tls-restricted-pr-test-parametrized.yaml
index 3525bb7..954377a 100644
--- a/mbed-tls-restricted-pr-test-parametrized.yaml
+++ b/mbed-tls-restricted-pr-test-parametrized.yaml
@@ -67,13 +67,11 @@
           Run TF-PSA-Crypto all.sh tests - Only enable if both TF_PSA_CRYPTO_REPO and TF_PSA_CRYPTO_BRANCH are set!
           Otherwise the test run will fail during BranchInfo gathering.
         name: RUN_TF_PSA_CRYPTO_ALL_SH
-    - 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
-        quickFilterEnabled: true
-        defaultValue: main
-        selectedValue: DEFAULT
+        default: main
+        trim: true
     pipeline-scm:
       lightweight-checkout: false
       scm:
diff --git a/mbedtls-release-ci-testing.yaml b/mbedtls-release-ci-testing.yaml
index 8f1701b..e22cfd9 100644
--- a/mbedtls-release-ci-testing.yaml
+++ b/mbedtls-release-ci-testing.yaml
@@ -66,13 +66,11 @@
         default: false
         description: Push head to coverity branch, triggering a scan (only done for the development branch)
         name: PUSH_COVERITY
-    - 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
-        quickFilterEnabled: true
-        defaultValue: main
-        selectedValue: DEFAULT
+        default: main
+        trim: true
     - string:
         name: TEST_PASS_EMAIL_ADDRESS
         description: E-mail addresses (delimited by ,) that a report should be sent to when the test run passes