completion/alias: fix test loading

If we're testing the *load*, then we need to `run` the load. If not, then the assert functions can't test it properly.

test/plugins/alias-completion.plugin.bats

@@ -8,7 +8,7 @@ function local_setup() {
 
 @test "alias-completion: See that aliases with double quotes and brackets do not break the plugin" {
   alias gtest="git log --graph --pretty=format:'%C(bold)%h%Creset%C(magenta)%d%Creset %s %C(yellow)<%an> %C(cyan)(%cr)%Creset' --abbrev-commit --date=relative"
-  load ../../plugins/available/alias-completion.plugin
+  run load ../../plugins/available/alias-completion.plugin
 
   assert_success
 }
@@ -24,5 +24,5 @@ function local_setup() {
   alias rm='rm -v'
   run load ../../plugins/available/alias-completion.plugin
 
-  refute_output
+  assert_output ""
 }