feat: get the runner version from a file

.codspeed-runner-version

@@ -0,0 +1 @@
+2.2.0

action.yml

@@ -24,8 +24,7 @@ inputs:
 
   runner-version:
     description: "The version of the runner to use"
-    default: "2.2.0"
-    required: true
+    required: false
 
   instruments:
     description: |
@@ -45,6 +44,12 @@ runs:
       run: |
         # Configure and run codspeed-runner
 
+        if [ -n "${{ inputs.runner-version }}" ]; then
+          RUNNER_VERSION="${{ inputs.runner-version }}"
+        else
+          RUNNER_VERSION=$(cat .codspeed-runner-version)
+        fi
+
         # Get the runner arguments
         RUNNER_ARGS=""
         if [ -n "${{ inputs.token }}" ]; then
@@ -64,12 +69,12 @@ runs:
         fi
 
         # Install the CodSpeedHQ/runner
-        head_status=$(curl -I -fsSL -w "%{http_code}" -o /dev/null https://github.com/CodSpeedHQ/runner/releases/download/v${{ inputs.runner-version }}/codspeed-runner-installer.sh)
+        head_status=$(curl -I -fsSL -w "%{http_code}" -o /dev/null https://github.com/CodSpeedHQ/runner/releases/download/v$RUNNER_VERSION/codspeed-runner-installer.sh)
         if [ "$head_status" -eq 404 ]; then
-          echo "Error: Version ${{ inputs.runner-version }} is not available in https://github.com/CodSpeedHQ/runner/releases, please a correct version."
+          echo "Error: Version $RUNNER_VERSION is not available in https://github.com/CodSpeedHQ/runner/releases, please a correct version."
           exit 1
         else
-          curl -fsSL https://github.com/CodSpeedHQ/runner/releases/download/v${{ inputs.runner-version }}/codspeed-runner-installer.sh | bash -s -- --quiet
+          curl -fsSL https://github.com/CodSpeedHQ/runner/releases/download/v$RUNNER_VERSION/codspeed-runner-installer.sh | bash -s -- --quiet
         fi
 
         # Run the benchmarks