RFR: 8286873: Improve websocket test execution time [v3]

[Daniel Jeliński]

> This PR improves the execution time of jdk_net tests (and, by extension, tier2) by about 3 minutes.
> 
> Tests located under `jdk/java/net/httpclient/websocket` are never run in parallel. Each of the 8 modified `Pending***` tests originally required 40 seconds to complete. After the proposed changes, they usually complete in 15 seconds.
> 
> This PR modifies the tests to initially run with 1 second timeout. If the test fails with 1 second timeout, it is retried with timeout increased to 10 seconds (the original value).
> 
> The modified tests were executed at least 10 times on each of: Windows, Linux (both x64 and aarch64), MacOS (both x64 and aarch64). No failures were observed.

Daniel Jeliński has updated the pull request incrementally with one additional commit since the last revision:

  Make it clear that both actions hang

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/8746/files
  - new: https://git.openjdk.java.net/jdk/pull/8746/files/bd7d3298..832d7f9a

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8746&range=02
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8746&range=01-02

  Stats: 24 lines in 9 files changed: 6 ins; 9 del; 9 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8746.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8746/head:pull/8746

PR: https://git.openjdk.java.net/jdk/pull/8746