Disable ruby-test-mri-linux-aarch64 for now, it times out too often

ci.jsonnet

@@ -528,7 +528,7 @@ local composition_environment = utils.add_inclusion_tracking(part_definitions, "
       "ruby-test-fast-linux-amd64":     $.platform.linux  + $.jdk.stable + $.env.jvm + gate + $.run.test_fast + { timelimit: "45:00" },  # To catch missing slow tags
       "ruby-test-mri-asserts":          $.platform.linux  + $.jdk.stable + $.env.jvm + gate + $.run.test_mri_fast + { timelimit: "01:15:00" },
       "ruby-test-mri-linux-amd64":      $.platform.linux  + $.jdk.stable + $.env.native + gate + $.run.test_mri + { timelimit: "01:20:00" },
-      "ruby-test-mri-linux-aarch64":    $.platform.linux_aarch64 + $.jdk.stable + $.env.native + gate + $.run.test_mri + { timelimit: "01:30:00" },
+      # "ruby-test-mri-linux-aarch64":  $.platform.linux_aarch64 + $.jdk.stable + $.env.native + gate + $.run.test_mri + { timelimit: "01:30:00" }, # GR-51361
       "ruby-test-mri-darwin-amd64":     $.platform.darwin_amd64 + $.jdk.stable + $.env.native + gate + $.run.test_mri + { timelimit: "01:30:00" },
       "ruby-test-mri-darwin-aarch64":   $.platform.darwin_aarch64 + $.jdk.stable + $.env.native + gate + $.run.test_mri + { timelimit: "01:30:00" },
       "ruby-test-integration-linux-amd64": $.platform.linux  + $.jdk.stable + $.env.jvm + gate + $.run.test_integration,