[czj]

Crafted request headers can no longer grow a process for good or make it raise.

Fixed

• Version checks no longer fill RubyGems' process-wide Gem::Version cache: 20,000 user agents with unique macOS
  versions grew a process by 200 MB.
• An Accept-Language header listing more than 32 languages is parsed on each request instead of cached: 1,000 such
  headers held 107 MB.
• Bytes that are not valid UTF-8 in the user agent or the Accept-Language header become U+FFFD instead of raising
  ArgumentError, and such client hints and Cloudflare headers are ignored.
• Browser.new checks the size of the user agent before reading it, so an oversized one is rejected in microseconds.

Once merged, bin/release tags the merge commit v3.1.1, which publishes the gem.