RFR: 8281511: java/net/ipv6tests/UdpTest.java fails with checkTime failed [v6]

[serhiysachkov]

> switching to nanoTime as suggested in ticket comments

serhiysachkov has updated the pull request incrementally with three additional commits since the last revision:

 - Update test/jdk/java/net/ipv6tests/UdpTest.java
   
   Co-authored-by: Daniel Fuchs <67001856+dfuch at users.noreply.github.com>
 - Update test/jdk/java/net/ipv6tests/UdpTest.java
   
   Co-authored-by: Daniel Fuchs <67001856+dfuch at users.noreply.github.com>
 - Update test/jdk/java/net/ipv6tests/UdpTest.java
   
   Co-authored-by: Daniel Fuchs <67001856+dfuch at users.noreply.github.com>

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/23840/files
  - new: https://git.openjdk.org/jdk/pull/23840/files/9f33f1f8..bcc43489

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23840&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23840&range=04-05

  Stats: 5 lines in 1 file changed: 0 ins; 0 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/23840.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23840/head:pull/23840

PR: https://git.openjdk.org/jdk/pull/23840