Custom sccache support in CI

.github/actions/setup/sccache.sh

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+
+# Get latest sccache version
+get_sccache_ver() {
+  curl -sL 'https://api.github.com/repos/mozilla/sccache/releases/latest' | jq -r .name
+}
+
+# $1=variant
+# $2=install_dir
+# $3=exe
+install_from_gh() {
+  local ver=$(curl -sL 'https://api.github.com/repos/mozilla/sccache/releases/latest' | jq -r .name)
+  local url="https://github.com/mozilla/sccache/releases/download/${ver}/sccache-${ver}-$1.tar.gz"
+  local dest="$2/$3"
+  curl -L "$url" | tar xz -O --wildcards "*/$3" > $dest
+  chmod +x $dest
+}
+
+if [ $RUNNER_OS = "macOS" ]; then
+  brew install sccache
+elif [ $RUNNER_OS = "Linux" ]; then
+  install_from_gh x86_64-unknown-linux-musl /usr/local/bin sccache
+elif [ $RUNNER_OS = "Windows" ]; then
+  install_from_gh x86_64-pc-windows-msvc $USERPROFILE/.cargo/bin sccache.exe
+fi