docs: Credential management documentation (#3147)

* docs: Create credential management documentation

* docs: Copy edits

* docs: Update graphics

* docs: Additional copy edits

* docs: Fix typos

* docs: Reduce size of graphics

* docs: Fix pixel density in brokering graphic

* docs: Increase size of graphics

* docs: Fix pixel density in brokering graphic

* docs: Fix issue with brokering image size

* docs: Adjust cred brokering image width

* docs: Adjust width of brokering graphic

* docs: Specify width for gifs

* docs: Undo width settings on gifs

* docs: Test brokering gif at 75%

* doc: Test resized images in preview deployment

* docs: Resize gifs smaller

* docs: Resize gifs a bit larger

* doc: Cleanup extra graphics, test zoomable link

* docs: Test gif loop with original

* docs: Update gif with loop, fix legacy link

* docs: Clean up file names, add updated graphics

* docs: Increase size of terminal gif

* docs: Update terminal graphic

* docs: Update with larger terminal graphic

* docs: Move large graphics to DatoCMS

website/data/docs-nav-data.json

@@ -211,6 +211,10 @@
         "title": "Service Discovery",
         "path": "concepts/service-discovery"
       },
+      {
+        "title": "Credential Management",
+        "path": "concepts/credential-management"
+      },
       {
         "title": "Security",
         "routes": [