RFR: 8263729: [test] Extend time to wait before destroying child in ProcssBuilder Basic test

[Roger Riggs]

Intermittent failures on Windows in a test of destroying the child warrant extending the time the parent waits after starting the child before destroying the child.

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Commit messages:
 - 8263729: [test] Extend time to wait before destroying child in ProcessBuilder Basic test

Changes: https://git.openjdk.java.net/jdk/pull/3049/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3049&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8263729
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3049.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3049/head:pull/3049

PR: https://git.openjdk.java.net/jdk/pull/3049