Remove direct usage of sun.misc.Signal

[pan3793]

Why are the changes needed?

This PR replaces the sun.misc.Signal with the Kyuubi wrapped one, see apache/kyuubi-shaded#64, which allows Kyuubi to use any of Java 8+ to compile with -release:8 while still ensuring compatibility with Java 8.

How was this patch tested?

Pass GHA.

Local tested by building against JDK 21, running on JDK 8, everything works as expected.

Was this patch authored or co-authored using generative AI tooling?

No.

[pan3793]

cc @bowenliang123 @LuciferYang

[bowenliang123]

LGTM

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 3 lines in your changes missing coverage. Please review.

Project coverage is 0.00%. Comparing base (97f0bae) to head (2eb2635).
Report is 2 commits behind head on master.

Files with missing lines	Patch %	Lines
.../scala/org/apache/kyuubi/util/SignalRegister.scala	0.00%	3 Missing ⚠️

Additional details and impacted files

@@          Coverage Diff           @@
##           master   #7144   +/-   ##
======================================
  Coverage    0.00%   0.00%           
======================================
  Files         701     701           
  Lines       43501   43501           
  Branches     5895    5895           
======================================
  Misses      43501   43501           

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