feat: add organization details to audit log response (#13961)

* Allow creating test audits with nil org

Not all audit entries have organization IDs, so this will allow us to
test those cases.

* Add organization details to audit log queries

* Add organization to audit log response

This replaces the old ID.  This is a breaking change but organizations
were not being used before.

coderd/apidoc/docs.go

@@ -8368,7 +8368,11 @@ const docTemplate = `{
                 "is_deleted": {
                     "type": "boolean"
                 },
+                "organization": {
+                    "$ref": "#/definitions/codersdk.MinimalOrganization"
+                },
                 "organization_id": {
+                    "description": "Deprecated: Use 'organization.id' instead.",
                     "type": "string",
                     "format": "uuid"
                 },
@@ -10102,6 +10106,27 @@ const docTemplate = `{
                 }
             }
         },
+        "codersdk.MinimalOrganization": {
+            "type": "object",
+            "required": [
+                "id"
+            ],
+            "properties": {
+                "display_name": {
+                    "type": "string"
+                },
+                "icon": {
+                    "type": "string"
+                },
+                "id": {
+                    "type": "string",
+                    "format": "uuid"
+                },
+                "name": {
+                    "type": "string"
+                }
+            }
+        },
         "codersdk.MinimalUser": {
             "type": "object",
             "required": [