Ensure that tests are optional (#3922)

var/spack/repos/builtin/packages/openblas/package.py

@@ -123,8 +123,8 @@ def build_targets(self):
 
         return self.make_defs + targets
 
-    @on_package_attributes(run_tests=True)
     @run_after('build')
+    @on_package_attributes(run_tests=True)
     def check_build(self):
         make('tests', *self.make_defs)
 
@@ -136,8 +136,8 @@ def install_targets(self):
         ]
         return make_args + self.make_defs
 
-    @on_package_attributes(run_tests=True)
     @run_after('install')
+    @on_package_attributes(run_tests=True)
     def check_install(self):
         spec = self.spec
         # Openblas may pass its own test but still fail to compile Lapack