test: change == to === in crypto test

Changed the equality comparison from == to identity operator ===

PR-URL: https://github.com/nodejs/node/pull/12405
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Vse Mozhet Byt <vsemozhetbyt@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Alexey Orlenko <eaglexrlnk@gmail.com>

test/parallel/test-crypto-sign-verify.js

@@ -139,7 +139,7 @@ const modSize = 1024;
                              padding: crypto.constants.RSA_PKCS1_PSS_PADDING,
                              saltLength: verifySaltLength
                            }, s4);
-          const saltLengthCorrect = getEffectiveSaltLength(signSaltLength) ==
+          const saltLengthCorrect = getEffectiveSaltLength(signSaltLength) ===
                                     getEffectiveSaltLength(verifySaltLength);
           assert.strictEqual(verified, saltLengthCorrect, 'verify (PSS)');
         });