Unpin google cloud sdk

Versions 312+ (current 320) fix issue that caused original pin

Build now takes longer so timeout was increased

kettle/Dockerfile

@@ -35,8 +35,9 @@ RUN pip3 install requests google-cloud-pubsub==2.1.0 google-cloud-bigquery==2.2.
 RUN curl -fsSL https://downloads.python.org/pypy/pypy3.6-v7.3.1-linux64.tar.bz2 | tar xj -C opt  && \
     ln -s /opt/pypy*/bin/pypy3 /usr/bin
 
-RUN curl https://dl.google.com/dl/cloudsdk/channels/rapid/downloads/google-cloud-sdk-294.0.0-linux-x86_64.tar.gz | tar xfz - -C . && \
-    ./google-cloud-sdk/install.sh -q && \
+RUN curl -o installer https://sdk.cloud.google.com && \
+    bash installer --disable-prompts --install-dir=/ && \
+    rm installer && \
     ln -s /google-cloud-sdk/bin/* /bin/
 
 ADD *.py schema.json runner.sh buckets.yaml /kettle/

kettle/cloudbuild.yaml

@@ -2,12 +2,12 @@ steps:
   - name: gcr.io/cloud-builders/docker
     args: [ 'build', '-t', 'gcr.io/$PROJECT_ID/kettle:$_GIT_TAG', '.' ]
     dir: kettle/
-    timeout: 1200s
+    timeout: 2000s
   - name: gcr.io/cloud-builders/docker
     args: [ 'tag', 'gcr.io/$PROJECT_ID/kettle:$_GIT_TAG', 'gcr.io/$PROJECT_ID/kettle:latest']
 substitutions:
   _GIT_TAG: '12345'
 images:
   - 'gcr.io/$PROJECT_ID/kettle:$_GIT_TAG'
   - 'gcr.io/$PROJECT_ID/kettle:latest'
-timeout: 1260s
+timeout: 2060s