GEODE-5830: Fix NONE enum for SSL configuration

[jujoramos]

GEODE-5830: Fix NONE enum for SSL configuration

The SecurableCommunicationChannel.NONE enum instance now references
the correct constant string, none, instead of NO_COMPONENT.

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[galen-pivotal]

This should be made a constant, SecurableCommunicationChannels.NONE, to be consistent with the other declarations.
I think I was wrong about this -- however, we have the other channels supported as a comma-separated list, and I don't think it makes sense to have none included as a member of that list.

[galen-pivotal]

This still fails the test from the GEODE ticket:

  @Test
  public void test() {
    final Properties properties = new Properties();
    properties.setProperty(ConfigurationProperties.SSL_ENABLED_COMPONENTS, "none");
    try (final Cache cache = new CacheFactory(properties).create()) {
    }

It should pass this test. Also, "none" should probably not work in conjunction with other components.

Another option (since no one actually seems to be using "none" as it doesn't work) would be to remove the mention of it from the docs and default to no components like we do now.

[jujoramos]

Agreed @galen-pivotal, I'll remove the none constant altogether and update the docs + tests.
Cheers.

[galen-pivotal]

Good cleanup and fix!

Per style guide, we need braces around all if statements. I left a comment inline. Apart from that, everything looks good.

[galen-pivotal]

Good cleanup here.

However, per the style guide, "Always use braces, even around one-line if, else and other control statements."

[galen-pivotal]

Suuuper minor grammatical suggestion: put a comma after "all", so that there are clearly three commma-separated options.

[galen-pivotal]

@jujoramos if you want, I'm happy to add the braces and merge. Just figured it might be helpful to get feedback on the style guide.

[jujoramos]

Hello @galen-pivotal,

I've made the changes, thanks.
Regarding the code style guide, I was aware of it but I keep seeing one-line control blocks without brackets in new commits, so I assumed that the style guide changed and never went a checked the link again, sorry about that :-). It'd be worth modifying the spotless plugin to enforce this rule, BTW.
I'll wait for the CI to finish and I'll merge the changes afterwards, thanks again!.
Cheers.