Fix OkHttpUtil.newDispatcher javadoc to state the concurrency bounds

[thswlsqls]

No closing keyword: #8316 also asks for RejectedExecutionException handling, which this javadoc-only change does not address, so it should stay open.

Description

• OkHttpUtil.newDispatcher() says the returned Dispatcher matches the OkHttp default apart from using daemon threads, but that has not been true since Bound OkHttp sender dispatchers and surface rejections #8422 (9dd6c38e0), which changed the code and left the sentence behind.
• OkHttp's Dispatcher defaults to maxRequests = 64 and an executor with an unbounded maximum pool size; this method bounds both to max(availableProcessors, 5).
• That bound was requested during the Bound OkHttp sender dispatchers and surface rejections #8422 review to line the OkHttp sender up with JdkHttpSender.newExecutor(), so the javadoc now names it.
• Javadoc only — no code change. maxRequestsPerHost is left out because it is still OkHttp's own default.

Testing done

• Docs-only, test-exempt: no test added. OkHttpUtilTest.newDispatcher_isBounded(), added by Bound OkHttp sender dispatchers and surface rejections #8422, already asserts the max(availableProcessors, 5) bound the new javadoc describes.
• ./gradlew :exporters:sender:okhttp:check — 46 tests passed.
• docs/apidiffs/current_vs_latest/opentelemetry-exporter-sender-okhttp.txt is unchanged (japicmp does not read javadoc text).

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.29%. Comparing base (e2efec5) to head (a449dad).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##               main    #8759   +/-   ##
=========================================
  Coverage     91.29%   91.29%           
  Complexity    10498    10498           
=========================================
  Files          1006     1006           
  Lines         28338    28338           
  Branches       3581     3581           
=========================================
+ Hits          25870    25871    +1     
  Misses         1675     1675           
+ Partials        793      792    -1     

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[opentelemetry-pr-dashboard]

Pull request dashboard status

Waiting on the author · refreshed 2026-09-02 14:35 UTC

Move out of draft to request review.

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