[jdk11u-dev] RFR: 8217395: Update langtools shell tests to use ${EXE_SUFFIX}

[luchenlin]

I backport this for parity with 11.0.20-oracle.

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Commit messages:
 - Backport 6326bf224e1388f0ed2f55db6f182e14cdae8c31

Changes: https://git.openjdk.org/jdk11u-dev/pull/1928/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=1928&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8217395
  Stats: 4 lines in 1 file changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/1928.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/1928/head:pull/1928

PR: https://git.openjdk.org/jdk11u-dev/pull/1928