Bug 1604909: Switch condprof to use debian test image as base; r=tarek

The ppa we were using to get a python newer than 3.5 is no longer public.
Switch to a newer base image, that is on a distribution that provides python3.7
natively.

Differential Revision: https://phabricator.services.mozilla.com/D57659

--HG--
extra : moz-landing-system : lando

taskcluster/ci/condprof/kind.yml

@@ -74,10 +74,10 @@ jobs:
         run:
             using: run-task
             command: >-
-                $CONDPROF_ROOT/virtualenv/virtualenv.py -p python3.6 $CONDPROF_ROOT &&
+                $CONDPROF_ROOT/virtualenv/virtualenv.py -p python3.7 $CONDPROF_ROOT &&
                 cd $CONDPROF_ROOT &&
                 export PATH="$PATH:$MOZ_FETCHES_DIR/bin" &&
-                bin/python3.6 condprof/runner.py --firefox $MOZ_FETCHES_DIR/firefox/firefox-bin $CONDPROF_ARCHIVES
+                bin/python3.7 condprof/runner.py --firefox $MOZ_FETCHES_DIR/firefox/firefox-bin $CONDPROF_ARCHIVES
         worker:
             docker-image: {in-tree: condprof}
             artifacts:

taskcluster/ci/docker-image/kind.yml

@@ -241,7 +241,7 @@ jobs:
         parent: debian9-base
     condprof:
         symbol: I(condprof)
-        parent: desktop1604-test
+        parent: debian10-test
     webrender-updater:
         symbol: I(wrupdater)
         parent: debian9-base

taskcluster/docker/condprof/Dockerfile

@@ -7,10 +7,8 @@ VOLUME /builds/worker/checkouts
 VOLUME /builds/worker/tooltool-cache
 VOLUME /builds/worker/workspace
 
-RUN add-apt-repository ppa:jonathonf/python-3.6
 RUN apt-get -y update && \
-    apt-get install -y python3.6 && \
-    curl https://bootstrap.pypa.io/get-pip.py | python3.6
+    apt-get install -y python3.7
 
 CMD ["/bin/bash", "--login"]