[Test] Increase length of test password for FIPS (#86948)

Password must be at least 114 bits in FIPS mode. This PR fixes the
password length in the new ServerCliTests so it passes in FIPS mode.

Relates: #85758 

PS: The test
[failed](https://gradle-enterprise.elastic.co/s/mrlw6o27onxee/tests/:distribution:tools:server-cli:test/org.elasticsearch.server.cli.ServerCliTests/testKeystorePassword)
on my PR CI.

distribution/tools/server-cli/src/test/java/org/elasticsearch/server/cli/ServerCliTests.java

@@ -251,7 +251,7 @@ public void assertKeystorePassword(String password) throws Exception {
     public void testKeystorePassword() throws Exception {
         assertKeystorePassword(null); // no keystore exists
         assertKeystorePassword("");
-        assertKeystorePassword("dummypassword");
+        assertKeystorePassword("a-dummy-password");
     }
 
     public void testCloseStopsServer() throws Exception {