Limit scheduled jobs to only run in iree-org. (#60)

These jobs are still runnable in forks via `pull_request` and
`workflow_dispatch` triggers, but this still skip the `schedule`
triggers in forks that do not have the workflows or scheduled jobs
disabled.

Most jobs are currently fast and use free resources, but the new
sharktank model tests do use git LFS quota, so we want to limit wasteful
usage there to avoid issues like
#56.

.github/workflows/test_linalg_ops.yml

@@ -31,6 +31,7 @@ concurrency:
 
 jobs:
   test-linalg-ops:
+    if: ${{ github.repository_owner == 'iree-org' || github.event_name != 'schedule' }}
     runs-on: ubuntu-24.04
     env:
       BUILD_DIR: build

.github/workflows/test_onnx_models.yml

@@ -31,6 +31,7 @@ concurrency:
 
 jobs:
   test-onnx-models:
+    if: ${{ github.repository_owner == 'iree-org' || github.event_name != 'schedule' }}
     runs-on: ubuntu-24.04
     env:
       VENV_DIR: ${{ github.workspace }}/.venv
@@ -67,4 +68,4 @@ jobs:
         uses: actions/upload-artifact@v4
         with:
           name: onnx_models_test_report_cpu_llvm_task.html
-          path: ${{ env.HTML_REPORT_PATH }}
+          path: ${{ env.HTML_REPORT_PATH }}

.github/workflows/test_onnx_ops.yml

@@ -31,6 +31,7 @@ concurrency:
 
 jobs:
   test-onnx-ops:
+    if: ${{ github.repository_owner == 'iree-org' || github.event_name != 'schedule' }}
     runs-on: ubuntu-24.04
     env:
       VENV_DIR: ${{ github.workspace }}/.venv

.github/workflows/test_sharktank_models.yml

@@ -31,6 +31,7 @@ concurrency:
 
 jobs:
   test-sharktank-models:
+    if: ${{ github.repository_owner == 'iree-org' || github.event_name != 'schedule' }}
     runs-on: ubuntu-24.04
     env:
       VENV_DIR: ${{ github.workspace }}/.venv