Add TMT gating plan

This adds a TMT plan for the gating test, which will currently
run a smoke tests only that are defined in the coreos-installer upstream
repository: https://github.com/coreos/coreos-installer
Verify the upstream repository PR for additional refrence:
https://github.com/coreos/coreos-installer/pull/1664

JIRA: https://issues.redhat.com/browse/COS-2286

Signed-off-by: Tiago Bueno <tbueno@redhat.com>

.fmf/version

@@ -0,0 +1 @@
+1

gating.yaml

@@ -3,4 +3,5 @@ product_versions:
   - rhel-10
 decision_context: osci_compose_gate
 rules:
-  - !PassingTestCaseRule {test_case_name: osci.brew-build.tier0.functional}
+  - !PassingTestCaseRule {test_case_name: osci.brew-build./tests/tmt/plans/smoke}
+

tests/tmt/plans/main.fmf

@@ -0,0 +1,12 @@
+---
+prepare:
+  - name: Install coreos-installer package
+    how: install
+    package: coreos-installer
+
+  - name: Set COS_INSTALLER_BIN_DIR when installed package
+    how: shell
+    script: |
+      set -x -e -o pipefail
+      echo "COS_INSTALLER_BIN_DIR=/usr/bin" > /tmp/cos_installer_bin_dir
+

tests/tmt/plans/smoke.fmf

@@ -0,0 +1,12 @@
+---
+summary: Run gating tests
+tag: 
+  - smoke
+discover:
+    - name: Internal gating tests
+      how: fmf
+      url: https://github.com/coreos/coreos-installer.git
+      filter: 'tag: smoke'
+execute:
+    how: tmt
+