Add support for eden_version input in test workflow

When the workflow is triggered from the outside, action/checkout
defaults to checking out the latest master which is not always desired.
For better compatibility with older EVE release the user should be able
to specify the version of eden to be used in the test workflow. If no
version is specified, the workflow should resert to the default behavior.

Signed-off-by: Paul Gaiduk <paulg@zededa.com>

.github/workflows/test.yml

@@ -1,9 +1,13 @@
 ---
 name: Test
 
-on:
+on:  # yamllint disable-line rule:truthy
   workflow_dispatch:
     inputs:
+      eden_version:
+        type: string
+        required: false
+        default: ''  # if not provided: When checking out the repository that triggered a workflow, this defaults to the reference or SHA for that event. Otherwise, uses the default branch.
       eve_image:
         type: string
       eve_artifact_name:
@@ -49,6 +53,7 @@ jobs:
         uses: actions/checkout@v3.5.3
         with:
           repository: "lf-edge/eden"
+          ref: ${{ inputs.eden_version }}
           path: "./eden"
       - name: Run Smoke tests
         uses: ./eden/.github/actions/run-eden-test
@@ -69,6 +74,7 @@ jobs:
         uses: actions/checkout@v3.5.3
         with:
           repository: "lf-edge/eden"
+          ref: ${{ inputs.eden_version }}
           path: "./eden"
       - name: Run Networking tests
         uses: ./eden/.github/actions/run-eden-test
@@ -93,6 +99,7 @@ jobs:
         uses: actions/checkout@v3.5.3
         with:
           repository: "lf-edge/eden"
+          ref: ${{ inputs.eden_version }}
           path: "./eden"
       - name: Run Storage tests
         uses: ./eden/.github/actions/run-eden-test
@@ -113,6 +120,7 @@ jobs:
         uses: actions/checkout@v3.5.3
         with:
           repository: "lf-edge/eden"
+          ref: ${{ inputs.eden_version }}
           path: "./eden"
       - name: Run LPC LOC tests
         uses: ./eden/.github/actions/run-eden-test
@@ -137,6 +145,7 @@ jobs:
         uses: actions/checkout@v3.5.3
         with:
           repository: "lf-edge/eden"
+          ref: ${{ inputs.eden_version }}
           path: "./eden"
       - name: Run EVE upgrade tests
         uses: ./eden/.github/actions/run-eden-test
@@ -157,6 +166,7 @@ jobs:
         uses: actions/checkout@v3.5.3
         with:
           repository: "lf-edge/eden"
+          ref: ${{ inputs.eden_version }}
           path: "./eden"
       - name: Run User apps upgrade tests
         uses: ./eden/.github/actions/run-eden-test