ci: remove auto-assign action (#1071)

not needed

.github/workflows/auto-assign.yml

@@ -1,54 +0,0 @@
-name: Theme Assigner
-on:
-  issues:
-    types: [opened, edited]
-  pull_request:
-    types: [opened, edited]
-
-jobs:
-  assign:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/github-script@v7
-        with:
-          github-token: ${{ secrets.GITHUB_TOKEN }}
-          script: |
-            const keywordsToAssigneesMap = {
-              BurntSienna: ["pjaspinski"],
-              Default: ["Blacksuan19"],
-              Dreary: ["CharlieS1103"],
-              Dribbblish: ["khanhas"],
-              Glaze: ["CharlieS1103"],
-              Onepunch: ["okarin001"],
-              Sleek: ["harbassan"],
-              Turntable: ["grasonchan"],
-              Ziro: ["schnensch0"],
-              Flow: ["ian-Liaozy", "Ruixi-Zhang"],
-              Matte: ["darkthemer"],
-              Blossom: ["Robatortas"],
-              Nightlight: ["iTenerai"],
-            };
-
-            const issue = await github.rest.issues.get({
-              owner: context.repo.owner,
-              repo: context.repo.repo,
-              issue_number: context.issue.number,
-            });
-
-            const title = issue.data.title;
-            const body = issue.data.body;
-
-            const assignees = [];
-
-            for (const [keyword, assignee] of Object.entries(keywordsToAssigneesMap)) {
-              if (title.match(new RegExp(`\\b${keyword}\\b`, "i")) || body.match(new RegExp(`\\b${keyword}\\b`, "i"))) {
-                assignees.push(...assignee);
-              }
-            }
-
-            await github.rest.issues.addAssignees({
-              owner: context.repo.owner,
-              repo: context.repo.repo,
-              issue_number: context.issue.number,
-              assignees: assignees,
-            });