use s1-prod-macos-arm64 build agent (confluentinc#1428)

* use s1-prod-macos-arm64 build agent
* use $WORKSPACE instead of $SEM_WORKSPACE

Author: cchristous

.semaphore/semaphore.yml

@@ -1,18 +1,18 @@
 version: v1.0
 name: Test on PR or create and upload wheels on tag.
-agent:
-  machine:
-    type: s1-prod-mac-m1
 global_job_config:
   secrets:
     - name: vault_sem2_approle
   env_vars:
     - name: LIBRDKAFKA_VERSION
       value: v1.9.2
+  prologue:
+    commands:
+      - checkout
+      - export HOME=$WORKSPACE
+      - cd $WORKSPACE/confluent-kafka-python
 blocks:
   - name: "Wheels: OSX x64"
-    run:
-      when: "tag =~ '.*'"
     dependencies: []
     task:
       agent:
@@ -26,19 +26,15 @@ blocks:
       jobs:
         - name: Build
           commands:
-            - cd $SEM_WORKSPACE
-            - export HOME=$SEM_WORKSPACE
-            - checkout
-            # needed on the self-hosted agent
-            - if [ ! -d ./tools ]; then cd $SEM_WORKSPACE/confluent-kafka-python; fi
             - PIP_INSTALL_OPTIONS="--user" tools/wheels/build-wheels.sh "${LIBRDKAFKA_VERSION#v}" wheelhouse
             - tar -czf wheelhouse-macOS-${ARCH}.tgz wheelhouse
             - artifact push workflow wheelhouse-macOS-${ARCH}.tgz
   - name: "Wheels: OSX arm64"
-    run:
-      when: "tag =~ '.*'"
     dependencies: []
     task:
+      agent:
+        machine:
+          type: s1-prod-macos-arm64
       env_vars:
         - name: OS_NAME
           value: osx
@@ -49,11 +45,6 @@ blocks:
       jobs:
         - name: Build
           commands:
-            - cd $SEM_WORKSPACE
-            - export HOME=$SEM_WORKSPACE
-            - checkout
-            # needed on the self-hosted agent
-            - if [ ! -d ./tools ]; then cd $SEM_WORKSPACE/confluent-kafka-python; fi
             - PIP_INSTALL_OPTIONS="--user" tools/wheels/build-wheels.sh "${LIBRDKAFKA_VERSION#v}" wheelhouse
             - tar -czf wheelhouse-macOS-${ARCH}.tgz wheelhouse
             - artifact push workflow wheelhouse-macOS-${ARCH}.tgz
@@ -72,11 +63,6 @@ blocks:
       jobs:
         - name: Build
           commands:
-            - cd $SEM_WORKSPACE
-            - export HOME=$SEM_WORKSPACE
-            - checkout
-            # needed on the self-hosted agent
-            - if [ ! -d ./tools ]; then cd $SEM_WORKSPACE/confluent-kafka-python; fi
             # use a virtualenv
             - python3 -m venv _venv && source _venv/bin/activate
             - pip install -r docs/requirements.txt
@@ -90,4 +76,4 @@ blocks:
             - export DYLD_LIBRARY_PATH="$DYLD_LIBRARY_PATH:$PWD/$lib_dir"
             # install confluent-kafka
             - python setup.py build && python setup.py install
-            - make docs
+            - make docs