different cache for examples and remove population step

.github/workflows/tests.yml

@@ -37,55 +37,8 @@ jobs:
       - name: "Check C/C++ formatting changes"
         run: git diff --exit-code
 
-  conan-cache:
-    if: github.event.pull_request.draft == false
-    runs-on: ubuntu-latest
-    env:
-      HOST_TYPE: ci
-      REDIS_QUEUE_HOST: redis
-      REDIS_STATE_HOST: redis
-    container:
-      image: faasm/faabric:0.2.2
-    defaults:
-      run:
-        working-directory: /code/faabric
-    services:
-      redis:
-        image: redis
-    steps:
-      # --- Code update ---
-      - name: "Fetch ref"
-        run: git fetch origin ${GITHUB_REF}:ci-branch
-      - name: "Check out branch"
-        run: git checkout --force ci-branch
-      # --- Set-up ---
-      - name: "Ping redis"
-        run: redis-cli -h redis ping
-      # --- Cache based on Conan version and ExternalProjects cmake source
-      - name: Get Conan version
-        id: get-conan-version
-        run: |
-          echo "::set-output name=conan-version::$(conan --version | tr -d '[:alpha:] ')"
-        shell: bash
-      - name: Hash ExternalProjects
-        id: hash-external
-        run: |
-          echo "::set-output name=hash-external::$(sha256sum cmake/ExternalProjects.cmake | cut '-d ' -f 1)"
-        shell: bash
-      - uses: actions/cache@v2
-        with:
-          path: '~/.conan'
-          key: ${{ runner.os }}-${{ steps.get-conan-version.outputs.conan-version }}-${{ steps.hash-external.outputs.hash-external }}
-          restore-keys: |
-            ${{ runner.os }}-${{ steps.get-conan-version.outputs.conan-version }}-
-            ${{ runner.os }}-
-      # --- Build dependencies
-      - name: "Build dependencies to be shared by all sanitiser runs"
-        run: inv dev.cmake -b Debug
-
   tests:
     if: github.event.pull_request.draft == false
-    needs: [conan-cache]
     runs-on: ubuntu-latest
     env:
       HOST_TYPE: ci
@@ -151,7 +104,6 @@ jobs:
 
   examples:
     if: github.event.pull_request.draft == false
-    needs: [conan-cache]
     runs-on: ubuntu-latest
     env:
       HOST_TYPE: ci
@@ -185,8 +137,9 @@ jobs:
       - uses: actions/cache@v2
         with:
           path: '~/.conan'
-          key: ${{ runner.os }}-${{ steps.get-conan-version.outputs.conan-version }}-${{ steps.hash-external.outputs.hash-external }}
+          key: ${{ runner.os }}-${{ steps.get-conan-version.outputs.conan-version }}-${{ steps.hash-external.outputs.hash-external }}-release
           restore-keys: |
+            ${{ runner.os }}-${{ steps.get-conan-version.outputs.conan-version }}-${{ steps.hash-external.outputs.hash-external }}
             ${{ runner.os }}-${{ steps.get-conan-version.outputs.conan-version }}-
             ${{ runner.os }}-
       # --- Examples ---