[foreign-memaccess+abi] RFR: Fix typo in TestLayouts

[Maurizio Cimadamore]

There is name mismatch in a data provider in `TestLayouts` which causes the test to fail. This patch fixes it.

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Commit messages:
 - Fix typo in TestLayouts

Changes: https://git.openjdk.org/panama-foreign/pull/803/files
 Webrev: https://webrevs.openjdk.org/?repo=panama-foreign&pr=803&range=00
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/panama-foreign/pull/803.diff
  Fetch: git fetch https://git.openjdk.org/panama-foreign pull/803/head:pull/803

PR: https://git.openjdk.org/panama-foreign/pull/803