feat: Add tunnel by default (#4399)

* feat: Add tunnel by default

If an access URL is not specified, we will always tunnel.

This is from community-member feedback who exclaimed that
it's confusing having the default for `coder server` display
a warning message, and I agree.

There is very little (maybe none) in running `coder server`
without tunnel and without an access URL, so this seems like
overall a much better UX.

* Update install.sh

Co-authored-by: Ben Potter <ben@coder.com>

* Update docs/install/packages.md

Co-authored-by: Ben Potter <ben@coder.com>

* Fix reset pass test

* Fix e2e test

Co-authored-by: Ben Potter <ben@coder.com>

docker-compose.yaml

@@ -13,9 +13,6 @@ services:
       # that workspaces can reach. This cannot be localhost
       # or 127.0.0.1 for non-Docker templates!
       CODER_ACCESS_URL: "${CODER_ACCESS_URL}"
-      # Alternatively, you can enable CODER_TUNNEL for
-      # proof-of-concept deployments.
-      CODER_TUNNEL: "${CODER_TUNNEL:-false}"
     # If the coder user does not have write permissions on
     # the docker socket, you can uncomment the following
     # lines and set the group ID to one that has write