Install ccache on Linux and macOS CI builders

Author: trflynn89

build/ci/Dockerfile

@@ -9,6 +9,7 @@ ARG JDK_VERSION
 # Install base tools
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y \
+        ccache \
         curl \
         git \
         lcov \

build/ci/macos.yml

@@ -8,6 +8,10 @@ jobs:
       vmImage: macOS-10.15
 
     steps:
+    - script: |
+        brew install ccache
+      displayName: 'Dependencies'
+
     - template: setup.yml
 
     - script: |