Fix enhanced TMT testing for centos-stream

Resolves: rhbz#2182334

plans/public.fmf

@@ -0,0 +1,6 @@
+summary: Test plan that runs all tests from tests repo.
+discover:
+    how: fmf
+    url: https://src.fedoraproject.org/tests/expat.git
+execute:
+    how: tmt

plans/tier1-internal.fmf

@@ -0,0 +1,15 @@
+summary: CI plan, picks Tier1 tests, runs in beakerlib.
+discover:
+  - name: rhel
+    how: fmf
+    filter: 'tier: 1'
+    url: git://pkgs.devel.redhat.com/tests/expat
+  - name: fedora
+    how: fmf
+    filter: 'tier: 1'
+    url: "https://src.fedoraproject.org/tests/expat.git"
+execute:
+    how: tmt
+adjust:
+    enabled: false
+    when: distro == centos-stream-9