Fix AndroidProfiler and SentryTracer crashes

[romtsn]

📜 Description

A customer reported these 2 crashes internally, so this PR simply fixes/swallows them. Most likely they were caused by calling Sentry.close() in the middle of processing transactions.

• The synchronized in AndroidTransactionProfiler should actually fix the root cause, but I've also added the null check just to make sure
• For SentryTracer fix we just swallow the exception and finish the transaction immediately if we failed to schedule the finish timer

💚 How did you test it?

Manually and automated

📝 Checklist

• I reviewed the submitted code.
• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• I updated the docs if needed.
• Review from the native team if needed.
• No breaking change or entry added to the changelog.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

🔮 Next steps

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	289.02 ms	373.63 ms	84.61 ms
Size	1.72 MiB	2.28 MiB	570.67 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
46b1782	387.72 ms	458.74 ms	71.02 ms
1707044	338.80 ms	384.79 ms	46.00 ms

App size

Revision	Plain	With Sentry	Diff
46b1782	1.72 MiB	2.28 MiB	570.44 KiB
1707044	1.72 MiB	2.28 MiB	570.44 KiB

[codecov]

Codecov Report

Patch coverage: 92.30% and project coverage change: +0.01 🎉

Comparison is base (a485ab0) 81.11% compared to head (c4f49fc) 81.13%.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2731      +/-   ##
============================================
+ Coverage     81.11%   81.13%   +0.01%     
- Complexity     4447     4449       +2     
============================================
  Files           345      345              
  Lines         16394    16402       +8     
  Branches       2226     2226              
============================================
+ Hits          13298    13307       +9     
  Misses         2168     2168              
+ Partials        928      927       -1     

Impacted Files	Coverage Δ
sentry/src/main/java/io/sentry/SentryTracer.java	94.96% <92.30%> (+0.51%)	⬆️

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