Release 6.0.21

• [Python] Fix version of Python when imp module is replaced with importlib. Contributed by Grigory Ponomarenko.
• [Ubuntu] Remove packages for Ubuntu 23.10 "mantic".
• [Nginx] Upgrades preferred Nginx to 1.26.0 from 1.24.0.
• [Nginx] Switch to using PCRE2 instead of PCRE.
• [RPM] The Passenger Nginx module rpm package for EL9 (RHEL, Rocky, Alma) will now require Nginx 1.24.0 as per the policy of supporting the newest Nginx module stream available.
• [Standalone] Fixes security update checker with builtin engine.
• [Enterprise] Ability to enforce hard memory limits on application processes (PassengerHardMemoryLimit/passenger_hard_memory_limit/`--hard-memory-limit``). Unlike the soft memory limit, the hard memory limit doesn't wait for the request to finish. Useful for preventing high memory usage from taking down the entire machine or container.
• [Enterprise] Ability to throttle memory metrics collection (PassengerAnalyticsCollectionRate/passenger_analytics_collection_rate). This allows you to control the frequency that Passenger Enterpprise measures the app memory use at.
• Swaps http-parser for llhttp.
• Fixes crash-watch hanging when lldb is used as backend.
• Fixes Apache module unload crash due to not properly cleaning up all threads.
• Workaround compilation error on clang on x86_64.
• Upgrades Boost from 1.83 -> 1.85.
• Updated various library versions used in precompiled binaries (used for e.g. gem installs):
  • ccache: 4.6.3 -> 4.9.1
  • cmake: 3.28.1 -> 3.29.3
  • curl: 8.5.0 -> 8.7.1
  • git: 2.43.0 -> 2.45.0
  • gnupg: 2.4.3 -> 2.4.5
  • libassuan: 2.5.6 -> 2.5.7
  • libffi: 3.4.4 -> 3.4.6
  • libgpg_error: 1.47 -> 1.49
  • libksba: 1.6.5 -> 1.6.6
  • libpsl: 0.21.5
  • npth: 1.6 -> 1.7
  • openssl: 3.2.0 -> 3.3.0
  • pcre2: 10.42 -> 10.43
  • pinentry: 1.2.1 -> 1.3.0
  • rubygems: 3.5.4 -> 3.5.10
  • zlib: 1.3 -> 1.3.1
  • zstd: 1.5.5 -> 1.5.6
  • rubies:
    • 3.0.6 -> 3.0.7
    • 3.1.4 -> 3.1.5
    • 3.2.3 -> 3.2.4
    • 3.3.0 -> 3.3.1