Bump JVM target to Java 17. Upgrade Jetty and Jersey.

[JonathanLennox]

No description provided.

[codecov]

Codecov Report

❌ Patch coverage is 0% with 13 lines in your changes missing coverage. Please review.
✅ Project coverage is 33.89%. Comparing base (2247444) to head (9ef38ed).

Files with missing lines	Patch %	Lines
...tty/src/main/kotlin/org/jitsi/rest/JettyHelpers.kt	0.00%	13 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master     #233      +/-   ##
============================================
- Coverage     34.04%   33.89%   -0.15%     
  Complexity      162      162              
============================================
  Files            36       36              
  Lines          1360     1366       +6     
  Branches        136      140       +4     
============================================
  Hits            463      463              
- Misses          864      870       +6     
  Partials         33       33              

Files with missing lines	Coverage Δ
...tty/src/main/kotlin/org/jitsi/rest/JettyHelpers.kt	0.00% <0.00%> (ø)

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[JonathanLennox]

Passing ci run is at jitsi/jicofo#1282