[llvm] [flang-rt] Update `test_flang` in CI to use `flang-rt` as one of the projects. (PR #135260)

[via llvm-commits]

github-actions[bot] wrote:

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:warning: Python code formatter, darker found issues in your code. :warning:

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``````````bash
darker --check --diff -r HEAD~1...HEAD .ci/compute_projects.py .ci/compute_projects_test.py
``````````

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View the diff from darker here.
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``````````diff
--- compute_projects_test.py	2025-04-10 20:08:12.000000 +0000
+++ compute_projects_test.py	2025-04-10 21:06:53.032562 +0000
@@ -138,11 +138,13 @@
 
     def test_flang(self):
         env_variables = compute_projects.get_env_variables(
             ["flang/CMakeLists.txt"], "Linux"
         )
-        self.assertEqual(env_variables["projects_to_build"], "clang;flang;llvm;flang-rt")
+        self.assertEqual(
+            env_variables["projects_to_build"], "clang;flang;llvm;flang-rt"
+        )
         self.assertEqual(env_variables["project_check_targets"], "check-flang")
         self.assertEqual(env_variables["runtimes_to_build"], "")
         self.assertEqual(env_variables["runtimes_check_targets"], "")
 
     def test_invalid_subproject(self):

``````````

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https://github.com/llvm/llvm-project/pull/135260