Fix `static_cache_control` deprecation warning

1. Fix the message by wrapping the value in missing quotes and adding
the missing backtick at the end. Finally, :lipstick: by adding a space
inside the curly braces.

Before:

`config.public_file_server.headers = {'Cache-Control' => public,
max-age=31536000}

Now:

`config.public_file_server.headers = { 'Cache-Control' => 'public,
max-age=31536000' }`

2. Display `static_cache_control` instead of static_cache_control. This
follows what the 2 neighboring methods are doing.

3. Use strip_heredoc to improve the code formatting and readability
like the 2 neighboring methods and wrap to 80 characters.

0 files changed, 0 insertions, 0 deletions