[jdk17u] RFR: 8274642: jdk/jshell/CommandCompletionTest.java fails with NoSuchElementException after JDK-8271287

[Martin Doerr]

Backport of JDK-8274642.

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Commit messages:
 - Backport 47262670f371923a704ec521da40010c2a46be5a

Changes: https://git.openjdk.java.net/jdk17u/pull/165/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17u&pr=165&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8274642
  Stats: 8 lines in 1 file changed: 6 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk17u/pull/165.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17u pull/165/head:pull/165

PR: https://git.openjdk.java.net/jdk17u/pull/165