[Backport to 0.34] Prevent a shutdown hook from being removed in JaegerTracer when a shutdown is in progress

[TomasHofman]

Prevent a shutdown hook from being removed in JaegerTracer when a shutdown is in progress

Signed-off-by: Tomas Hofman [email protected]

Which problem is this PR solving?

This is follow up PR for #679

The problem this PR is solving that when a JaegerTracer is closed as a result of shutdown, the attempt to remove its' close shutdown hook fails with IllegalStateException. I.e. the shutdown hook cannot be removed when shutdown is already in progress.

Short description of the changes

Do not remove a shutdown hook when a shutdown is already in progress.

[codecov]

Codecov Report

Merging #690 into release-0.34 will increase coverage by 0.15%.
The diff coverage is 100%.

@@                Coverage Diff                 @@
##             release-0.34     #690      +/-   ##
==================================================
+ Coverage           89.39%   89.55%   +0.15%     
- Complexity            542      543       +1     
==================================================
  Files                  68       68              
  Lines                1952     1953       +1     
  Branches              252      252              
==================================================
+ Hits                 1745     1749       +4     
+ Misses                131      129       -2     
+ Partials               76       75       -1

Impacted Files	Coverage Δ	Complexity Δ
...n/java/io/jaegertracing/internal/JaegerTracer.java	89.16% <100%> (+1.12%)	27 <0> (+1)	⬆️

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[yurishkuro]

looks like a duplicate of #689

[TomasHofman]

@yurishkuro this is for 0.34 stream. The original commit is in 0.34 too.