[jdk17u-dev] RFR: 8270837: fix typos in test TestSigParse.java

[Goetz Lindenmaier]

I backport this for parity with 17.0.4-oracle.

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Commit messages:
 - Backport 67dc1c5bf34cfe987b672f34f0b2a6b36840382a

Changes: https://git.openjdk.java.net/jdk17u-dev/pull/216/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17u-dev&pr=216&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8270837
  Stats: 3 lines in 1 file changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.java.net/jdk17u-dev/pull/216.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17u-dev pull/216/head:pull/216

PR: https://git.openjdk.java.net/jdk17u-dev/pull/216