dev: bump Alire version to 2.1.1 and setup-alire to @latest (#1942)

* dev: bump Alire to 2.1.1 and setup-alire to @latest

* Touch libhello

.github/workflows/check-index.yml

@@ -1,7 +1,7 @@
 name: Check Index
 
 env:
-  ALR_VERSION: 2.1.0
+  ALR_VERSION: 2.1.1
 
 on: pull_request
 
@@ -13,13 +13,13 @@ jobs:
 
     - name: Set up stable `alr`
       if: contains(github.base_ref, 'stable-')
-      uses: alire-project/setup-alire@v5
+      uses: alire-project/setup-alire@latest
       with:
         version: ${{env.ALR_VERSION}}
 
     - name: Set up devel `alr`
       if: contains(github.base_ref, 'devel-')
-      uses: alire-project/setup-alire@v5
+      uses: alire-project/setup-alire@latest
       with:
         branch: master