Fix documentation

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/tests/scripts/generate_psa_tests.py b/tests/scripts/generate_psa_tests.py
index 2ea3fd9..dcff50f 100755
--- a/tests/scripts/generate_psa_tests.py
+++ b/tests/scripts/generate_psa_tests.py
@@ -521,7 +521,7 @@
             key_type: psa_storage.Expr, bits: int,
             alg: psa_storage.Expr
     ) -> bool:
-        """Whether to the given key with the given algorithm.
+        """Whether to exercise the given key with the given algorithm.
 
         Normally only the type and algorithm matter for compatibility, and
         this is handled in crypto_knowledge.KeyType.can_do(). This function