ci: update to pnpm@9

Author: velut

.github/workflows/main.yml

@@ -17,7 +17,7 @@ jobs:
       - name: Setup pnpm
         uses: pnpm/action-setup@v3
         with:
-          version: 8
+          version: 9
 
       - name: Setup Node
         uses: actions/setup-node@v4

.github/workflows/not-main.yml

@@ -15,7 +15,7 @@ jobs:
       - name: Setup pnpm
         uses: pnpm/action-setup@v3
         with:
-          version: 8
+          version: 9
 
       - name: Setup Node
         uses: actions/setup-node@v4