Include runner name in cache key when using cargo for builds

If we're running cargo, we need to add the runner name to the cache. Otherwise things that link
against system packages, like openssl, can break when we use the same cache across different
versions of the runner OS. For example, when going from Ubuntu 20.04 to 22.04, we move from OpenSSL
1.1.x to 3.x.

action.yml

@@ -135,7 +135,7 @@ runs:
         set -o pipefail
         # This will get the inputs JSON from the `RUST_CACHE_PARAMETERS` env var. This avoids
         # any string interpolation issues, since the inputs will contain quotes.
-        parse-rust-cache-parameters.py "${{ inputs.target }}"
+        parse-rust-cache-parameters.py "${{ inputs.target }}" "${{ steps.set-build-command.outputs.build-command }}" "${{ runner.name }}"
       env:
         RUST_CACHE_PARAMETERS: ${{ inputs.rust-cache-parameters }}
       if: inputs.use-rust-cache == 'true'

parse-rust-cache-parameters.py

@@ -4,11 +4,22 @@
 import os
 import sys
 
+target = sys.argv[1]
+build_command = sys.argv[2]
+runner_name = sys.argv[3]
+
 parameters = json.loads(os.environ["RUST_CACHE_PARAMETERS"])
 if "key" not in parameters:
-    parameters["key"] = sys.argv[1]
+    parameters["key"] = target
 else:
-    parameters["key"] = "{}-{}".format(parameters["key"], sys.argv[1])
+    parameters["key"] = "{}-{}".format(parameters["key"], target)
+
+# If we're running cargo, we need to add the runner name to the cache. Otherwise things that link
+# against system packages, like openssl, can break when we use the same cache across different
+# versions of the runner OS. For example, when going from Ubuntu 20.04 to 22.04, we move from
+# OpenSSL 1.1.x to 3.x.
+if build_command == "cargo":
+    parameters["key"] = "{}-{}".format(parameters["key"], runner_name)
 
 file = os.environ["GITHUB_OUTPUT"]
 with open(file, "w") as f: