Running bin/logstash will produce a Gem::Specification.reset warning on startup

[robbavey]

Logstash information:

Please include the following information:

1. Logstash version (e.g. bin/logstash --version)
   main

2. Logstash installation source (e.g. built from source, with a package manager: DEB/RPM, expanded from tar or zip archive, docker)

Built from source

Steps to reproduce:

Please include a minimal but complete recreation of the problem,
including (e.g.) pipeline definition(s), settings, locale, etc. The easier
you make for us to reproduce it, the more likely that somebody will take the
time to look at it.

run bin/logstash

The following is printed on the command-line

robbavey@Robs-MacBook-Pro logstash % bin/logstash
Using system java: /Users/robbavey/.sdkman/candidates/java/current/bin/java
WARN: Unresolved or ambiguous specs during Gem::Specification.reset:
      date (>= 0)
      Available/installed versions of this gem:
      - 3.4.1
      - 3.3.3
WARN: Clearing out unresolved specs. Try 'gem cleanup <gem>'
Please report a bug if this causes problems.

[donoghuc]

Investigation/analysis as to why this just started happening now: #16753 (comment)

[robbavey]

Closed by #16755