Shorten display labels in CI jobs

GitHub currently labels each of the "Checks" workflow jobs on a PR
in the format: `${{ workflow.name }} / ${{ job.id }} (${ trigger }})`,
which leaves us with long labels like:
* `Label merge conflicts / conflicts (pull_request_target)`
* `REUSE Verification / lint (pull_request)`

This will (slightly) trim those down to:
* `Merge conflicts / label (pull_request_target)`
* `REUSE / verify (pull_request)`

.github/workflows/label-conflicts.yml

@@ -2,7 +2,7 @@
 #
 # SPDX-License-Identifier: GPL-2.0-or-later
 
-name: "Label merge conflicts"
+name: "Merge conflicts"
 on:
   # So that PRs touching the same files as the push are updated
   push:
@@ -17,7 +17,7 @@ on:
     types: [synchronize]
 
 jobs:
-  conflicts:
+  label:
     runs-on: ubuntu-latest
     permissions:
       pull-requests: write

.github/workflows/reuse.yml

@@ -2,7 +2,7 @@
 #
 # SPDX-License-Identifier: GPL-2.0-or-later
 
-name: REUSE Verification
+name: REUSE
 
 on:
   push:
@@ -14,7 +14,7 @@ on:
   workflow_dispatch:
 
 jobs:
-  lint:
+  verify:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4