Add missing details for APIML cookie config

[1000TurquoisePogs]

When adding compatibility in app-server for APIML's customizable cookie name, I needed to look up how it worked.
I found the document does not fully describe "zowe.cookieIdentifier"
It instead referenced a "cookieIdentifier", without stating what that was or where to find it.
I confirmed APIML's code really is referring to "zowe.cookieIdentifier" https://github.com/search?q=repo%3Azowe%2Fapi-layer%20cookieidentifier&type=code which is present in both v2 and v3 https://github.com/zowe/zowe-install-packaging/blob/v3.x/staging/example-zowe.yaml#L317

I updated the document for each version and made clarifications to help explain it.

[github-actions]

😺 Thank you for creating this PR! To publish your content to Zowe Docs, follow these required steps.

• Add the label review: doc.
• Identify your content topic with a label. (Examples: area: apiml, area: cli, area: install and config, etc.)
• Specify the major Zowe release(s) for your content. (Examples: release: V1, release: V2, release: V3)
  • If adding content that needs to be removed from V3 documentation, add the V3 N/A tag.
• Select the master branch if your PR updates content that is on the live site. Select docs-staging if your PR updates content for a future release.
• Notify the Doc Squad about this PR. If you don't know whom should review your content, message the #zowe-doc Slack channel. If you know which Doc Squad writer should approve your content, add that person as a reviewer.

Need help? Contact the Doc Squad in the #zowe-doc Slack channel.

[github-actions]

😺 Thank you for creating this PR! To publish your content to Zowe Docs, follow these required steps.

• Add the label review: doc.
• Identify your content topic with a label. (Examples: area: apiml, area: cli, area: install and config, etc.)
• Specify the major Zowe release(s) for your content. (Examples: release: V1, release: V2, release: V3)
  • If adding content that needs to be removed from V3 documentation, add the V3 N/A tag.
• Select the master branch if your PR updates content that is on the live site. Select docs-staging if your PR updates content for a future release.
• Notify the Doc Squad about this PR. If you don't know whom should review your content, message the #zowe-doc Slack channel. If you know which Doc Squad writer should approve your content, add that person as a reviewer.

Need help? Contact the Doc Squad in the #zowe-doc Slack channel.

[github-actions]

📁 The PR description is missing the file name(s) for the updated content. List all the files included in this PR so this information displays in our Zowe Docs GitHub Slack channel.

If you have addressed this issue already, refresh this page in your browser to remove this comment.

[github-actions]

📁 The PR description is missing the file name(s) for the updated content. List all the files included in this PR so this information displays in our Zowe Docs GitHub Slack channel.

If you have addressed this issue already, refresh this page in your browser to remove this comment.

[github-actions]

🚀 Deployed on https://673265e69f7552a34c116cef--zowe-docs-master.netlify.app

[anaxceron]

Thank you @1000TurquoisePogs. Made some comments re: clarity, grammar, style.

[anaxceron]

If someone needs to add this property, will they know where to add it? If not, should we specify the location?

[1000TurquoisePogs]

I believe so, but think about this:
"components.gateway.apiml.security.auth" exists here https://github.com/zowe/zowe-install-packaging/blob/v3.x/staging/example-zowe.yaml#L502-L511
So we're saying to add a sub-attribute called "uniqueCookie"

In many places of the doc, we use this "this.that.thing" format for brevity and every time devs interact with users.
I believe it's well understood in general and by enough exposure by now, but the concept is covered in this note in the YAML reference:
https://docs.zowe.org/v2.18.x/appendix/zowe-yaml-configuration

The only thing I can think to do to make it more apparent is to somehow be able to reference that appendix in every place where we make such YAML references. But, I don't think anyone agreed upon a good way to do that if at all.

[anaxceron]

@1000TurquoisePogs -- I think we can avoid linking to the appendix everywhere. We could link to the glossary since the definition includes a link to the appendix. I leave it to you, but my suggestion would be creating a link to the glossary term "Zowe configuration file":

1. Open the Zowe YAML configuration file

[anaxceron]

For the live site and previous versions: Avoid future tense in documentation: "This sets a suffix ... "

[1000TurquoisePogs]

Ok fixed!

[anaxceron]

For the live site and previous versions:

• Please add a definite article: "If the bbbb parameter is set ... "
• Avoid future tense: " ... the cookie name is blahblah."