RFR: 8304174: Remove delays from httpserver tests

[Daniel Jeliński]

This change improves the running time of many httpserver tests; it removes the one second delay introduced by `delay()` calls, and performs immediate httpserver stop by calling `stop(0)`.

For example, `com/sun/net/httpserver/Test1.java` usually takes 20-30 seconds without this change; with this change it completes in 5-8 seconds.

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Commit messages:
 - Update copyright
 - Remove delay when stopping server

Changes: https://git.openjdk.org/jdk/pull/13028/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13028&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8304174
  Stats: 111 lines in 40 files changed: 0 ins; 23 del; 88 mod
  Patch: https://git.openjdk.org/jdk/pull/13028.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/13028/head:pull/13028

PR: https://git.openjdk.org/jdk/pull/13028