feat(ci): Parameterize build task output

Potentially useful when using the task for release artifact building
later.

.ci/pipelines/pr.yml

@@ -32,6 +32,7 @@ jobs:
     file: repo/.ci/tasks/build.yml
     vars:
       target: msvc
+      output: artifact
       ref: ((.:ref))
       gitea_api_key: ((gitea_api_key))
 
@@ -45,5 +46,6 @@ jobs:
     file: repo/.ci/tasks/build.yml
     vars:
       target: linux
+      output: artifact
       ref: ((.:ref))
       gitea_api_key: ((gitea_api_key))

.ci/tasks/build.yml

@@ -11,14 +11,14 @@ inputs:
 - name: repo
 
 outputs:
-- name: artifact
+- name: ((output))
 
 params:
   CI: true
   TARGET: ((target))
   GITEA_API_KEY: ((gitea_api_key))
   REF: ((ref))
-  OUTPUT: artifact
+  OUTPUT: ((output))
 
 run:
   path: .ci/util/run.sh