Update FIPS hmac key documentation

The documentation is slightly incorrect about the FIPS hmac key.

CLA: trivial

Reviewed-by: Shane Lontis <shane.lontis@oracle.com>
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/23846)

INSTALL.md

@@ -530,7 +530,7 @@ Setting the FIPS HMAC key
 
 As part of its self-test validation, the FIPS module must verify itself
 by performing a SHA-256 HMAC computation on itself. The default key is
-the SHA256 value of "the holy handgrenade of antioch" and is sufficient
+the SHA256 value of "holy hand grenade of antioch" and is sufficient
 for meeting the FIPS requirements.
 
 To change the key to a different value, use this flag. The value should