fix: pass WOLFSSL_DIR as env var, not cmake -D

wychcheck's CMakeLists.txt reads WOLFSSL_DIR from the environment
($ENV{WOLFSSL_DIR}), which overwrites any -D cache variable. Pass it
as an env var so cmake picks it up correctly.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: MarkAtwood

.github/workflows/wycheproof.yml

@@ -62,8 +62,10 @@ jobs:
 
       - name: Build wolfcrypt-check
         working-directory: wychcheck
+        env:
+          WOLFSSL_DIR: ${{ github.workspace }}
         run: |
-          cmake -B build -DWOLFSSL_DIR=${{ github.workspace }}
+          cmake -B build
           cmake --build build -j$(nproc)
 
       - name: Run wycheproof tests