RFR: 8371475: HttpClient: Implement CUBIC congestion controller [v2]

[Daniel Jeliński]

>> CUBIC is a standard TCP congestion control algorithm that uses a cubic function instead of a linear congestion window increase function to improve scalability and stability over fast and long-distance networks. CUBIC has been adopted as the default TCP congestion control algorithm by the Linux, Windows, and Apple stacks.
> 
> This PR adds a new congestion controller algorithm. It reuses a large part of the QuicRenoCongestionController, which was refactored to two classes - QuicBaseCongestionController, containing the shared code, and QuicRenoCongestionController, containing only the code that is unique to Reno.
> 
> CUBIC is now the default congestion controller. Reno can still be selected by setting the system property `jdk.httpclient.quic.congestionController` to `reno`.
> 
> A new test was added to exercise the new congestion controller. Existing tests continue to pass.

Daniel Jeliński has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase.

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Changes:
  - all: https://git.openjdk.org/jdk/pull/28195/files
  - new: https://git.openjdk.org/jdk/pull/28195/files/b95950f2..b95950f2

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=28195&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=28195&range=00-01

  Stats: 0 lines in 0 files changed: 0 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/28195.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28195/head:pull/28195

PR: https://git.openjdk.org/jdk/pull/28195