Improve documentation for the yaml.schemas setting

Fixes #1147

Signed-off-by: David Thompson <davthomp@redhat.com>

Author: datho7561

package.json

@@ -120,7 +120,11 @@
         "yaml.schemas": {
           "type": "object",
           "default": {},
-          "description": "Associate schemas to YAML files in the current workspace"
+          "additionalProperties": {
+            "type": "string",
+            "markdownDescription": "- **Key**: The path or URL of the schema to use\n- **Value**: A glob pattern specifying which files the schema should be used on"
+          },
+          "markdownDescription": "Associate schemas to YAML files in the current workspace. The expected value of this configuration option is a string to string map:\n- **Key**: The path or URL of the schema to use\n- **Value**: A glob pattern specifying which files the schema should be used on"
         },
         "yaml.format.enable": {
           "type": "boolean",