gitlab-ci: only run Linux builds on-demand

.gitlab-ci.yml

@@ -41,7 +41,7 @@ build:linux-plain:
         - .cmake_build_linux
         - .cmake_build_artifacts
         - .linux_builder_tags
-        - .run_automatically
+        - .run_manually
 
 test:linux-plain:
     extends:
@@ -74,7 +74,7 @@ build:linux-egl:
         - .cmake_build_linux
         - .cmake_build_artifacts
         - .linux_builder_tags
-        - .run_automatically
+        - .run_manually
 
 test:linux-egl:
     extends:
@@ -108,7 +108,7 @@ build:linux-osmesa-shared:
         - .cmake_build_linux
         - .cmake_build_artifacts
         - .linux_builder_tags
-        - .run_automatically
+        - .run_manually
 
 test:linux-osmesa-shared:
     extends:
@@ -144,7 +144,7 @@ build:linux-osmesa-static:
         - .cmake_build_linux
         - .cmake_build_artifacts
         - .linux_builder_tags
-        - .run_automatically
+        - .run_manually
 
 test:linux-osmesa-static:
     extends: