Drop removed bundler flags

[davidtaylorhq]

No description provided.

[Supermathie]

should this not be bundle config set deployment true as per the error message?

[fitzy101]

Might be easier to use env BUNDLE_DEPLOYMENT=true bundle install .... instead of having to use the call bundle config set ... or have the --without test development and --path .. in the argument list.

e.g.

diff --git a/image/discourse_dev/Dockerfile b/image/discourse_dev/Dockerfile
index 9f9f4bf..fa42b65 100644
--- a/image/discourse_dev/Dockerfile
+++ b/image/discourse_dev/Dockerfile
@@ -66,7 +66,7 @@ USER discourse
 # Warm global bundle cache, then delete the compressed `cache/` versions (`/gem/` are enough)
 RUN --mount=type=bind,src=/repo,from=repo-fetcher,target=/tmp/discourse-clone,readwrite \
     cd /tmp/discourse-clone \
-    && bundle install --deployment \
+    && env BUNDLE_DEPLOYMENT=true bundle install \
     && rm -rf /home/discourse/.bundle/gems/ruby/*/cache/*
 
 # Warm global yarn cache