build: Lock GitHub runners' OS

This was motivated by our macOS jobs failing [2] because
colima is missing. It looks like this is because the
latest versions of the macOS runner no longer have
colima installed by default [1].

colima is now explicitly installed.

[1] actions/runner-images#6216
[2] `/Users/runner/work/_temp/f19ffbff-27a9-4fc7-80b6-97791d2de141.sh: line 9: colima: command not found`

.github/workflows/tests.yml

@@ -15,7 +15,7 @@ jobs:
       matrix:
         python-version: ["3.9", "3.10"]
         target: ["dataplane", "model-repository"]
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v4
       - name: Set up Python ${{ matrix.python-version }}
@@ -37,7 +37,7 @@ jobs:
     strategy:
       matrix:
         python-version: ["3.9", "3.10"]
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v4
       - name: Set up Python ${{ matrix.python-version }}
@@ -57,7 +57,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, macos-latest]
+        os: [ubuntu-22.04, macos-13]
         # NOTE: There's no pre-built `grpcio` wheel for Python 3.11 yet
         # https://github.com/grpc/grpc/issues/32454
         python-version: ["3.9", "3.10"]
@@ -67,7 +67,7 @@ jobs:
           # MacOS tests take a lot of time, so we will run them only on merge
           # From https://github.com/orgs/community/discussions/26253
           - is-pr: true
-            os: macos-latest
+            os: macos-13
     runs-on: ${{ matrix.os }}
     steps:
       - name: Setup docker (missing on MacOS)
@@ -81,6 +81,7 @@ jobs:
           brew install docker docker-buildx
           mkdir -p $HOME/.docker/cli-plugins
           ln -sfn $(which docker-buildx) $HOME/.docker/cli-plugins/docker-buildx
+          brew install colima
           colima start --memory 5 --network-driver slirp
           sudo ln -sf $HOME/.colima/default/docker.sock /var/run/docker.sock
       - uses: actions/checkout@v4
@@ -105,7 +106,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, macos-latest]
+        os: [ubuntu-22.04, macos-13]
         python-version: ["3.9", "3.10"]
         tox-environment:
           - sklearn
@@ -122,7 +123,7 @@ jobs:
           # MacOS tests take a lot of time, so we will run them only on merge
           # From https://github.com/orgs/community/discussions/26253
           - is-pr: true
-            os: macos-latest
+            os: macos-13
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v4
@@ -149,7 +150,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, macos-latest]
+        os: [ubuntu-22.04, macos-13]
         python-version: ["3.9", "3.10"]
     runs-on: ${{ matrix.os }}
     steps: