provisioning: Add expected example output

Add the expected example output so that we can automatically test that
the example is working as intended.

tests/provisioning.log

@@ -0,0 +1,45 @@
+Provisioning device...
+        Erasing secure storage... done.
+        Registering drivers... done.
+        Initializing PSA Crypto... done.
+        Registering factory-created keys... done.
+        Generating keys within the secure element... done.
+Device provisioned
+
+---------------------------------------------------------------------
+
+Device public keys:
+        Key ID 16:
+-----BEGIN PUBLIC KEY-----
+[0-9a-fA-F+/=]+
+[0-9a-fA-F+/=]+
+-----END PUBLIC KEY-----
+
+        Key ID 18:
+-----BEGIN PUBLIC KEY-----
+[0-9a-fA-F+/=]+
+[0-9a-fA-F+/=]+
+-----END PUBLIC KEY-----
+
+Device-generated CSRs:
+        Key ID 16:
+-----BEGIN CERTIFICATE REQUEST-----
+[0-9a-fA-F+/=]+
+[0-9a-fA-F+/=]+
+[0-9a-fA-F+/=]+
+[0-9a-fA-F+/=]+
+[0-9a-fA-F+/=]+
+[0-9a-fA-F+/=]+
+[0-9a-fA-F+/=]+
+-----END CERTIFICATE REQUEST-----
+
+        Key ID 18:
+-----BEGIN CERTIFICATE REQUEST-----
+[0-9a-fA-F+/=]+
+[0-9a-fA-F+/=]+
+[0-9a-fA-F+/=]+
+[0-9a-fA-F+/=]+
+[0-9a-fA-F+/=]+
+[0-9a-fA-F+/=]+
+[0-9a-fA-F+/=]+
+-----END CERTIFICATE REQUEST-----