feat: adds elixir support (#354)

Co-authored-by: Benjamin E. Coe <bencoe@google.com>

Author: thepiwo

README.md

@@ -87,6 +87,7 @@ Release Please automates releases for the following flavors of repositories:
 | ocaml             | [An OCaml repository, containing 1 or more opam or esy files and a CHANGELOG.md](https://github.com/grain-lang/binaryen.ml) |
 | `simple` | [A repository with a version.txt and a CHANGELOG.md](https://github.com/googleapis/gapic-generator) |
 | helm | A helm chart repository with a Chart.yaml and a CHANGELOG.md |
+| elixir | An elixir repository with a mix.exs and a CHANGELOG.md |
 
 ## How release please works
 

package-lock.json

@@ -26,7 +26,7 @@
   "homepage": "https://github.com/bcoe/release-please-action#readme",
   "dependencies": {
     "@actions/core": "^1.2.6",
-    "release-please": "^11.22.0"
+    "release-please": "^11.23.0"
   },
   "devDependencies": {
     "@vercel/ncc": "^0.27.0",