Migrate to TMT-style gating in C9S

This is required for RHIVOS, see VROOM-23635.

ci.fmf

@@ -0,0 +1 @@
+resultsdb-testcase: separate

gating.yaml

@@ -3,5 +3,4 @@ product_versions:
   - rhel-9
 decision_context: osci_compose_gate
 rules:
-  - !PassingTestCaseRule {test_case_name: osci.brew-build.tier0.functional}
+  - !PassingTestCaseRule {test_case_name: osci.brew-build./plans/bash.functional}
-  - !PassingTestCaseRule {test_case_name: baseos-ci.brew-build.tier1.functional}

plans/bash.fmf

@@ -0,0 +1,23 @@
+summary: Run internal bash tests
+discover:
+    - name: Internal bash gating tests (dash)
+      how: fmf
+      url: git://pkgs.devel.redhat.com/tests/dash
+      filter: 'tag: CI-Tier-1 & component: bash'
+    - name: Internal bash gating tests (bash)
+      how: fmf
+      url: git://pkgs.devel.redhat.com/tests/bash
+      filter: 'tag: CI-Tier-1 & component: bash'
+    - name: Internal bash gating tests (ksh)
+      how: fmf
+      url: git://pkgs.devel.redhat.com/tests/ksh
+      filter: 'tag: CI-Tier-1 & component: bash'
+    - name: Internal bash gating tests (zsh)
+      how: fmf
+      url: git://pkgs.devel.redhat.com/tests/zsh
+      filter: 'tag: CI-Tier-1 & component: bash'
+execute:
+    how: tmt
+adjust:
+    enabled: false
+    when: distro == centos-stream or distro == fedora