docs(api): name the unadopted-repository search parameter query (#39370)

`GET /admin/unadopted` documents a `pattern` query parameter, but the
handler reads `query`:

```go
repoNames, count, err := repo_service.ListUnadoptedRepositories(ctx, ctx.FormString("query"), &listOptions)
```

Nothing in the tree reads `pattern`. A client generated from the
published spec sends it, the server ignores it, and the caller gets the
full unadopted list with no error — the failure is silent.

Both spellings date from the commit that added the endpoint,
https://github.com/go-gitea/gitea/pull/12920, so the documentation has
been wrong since 2020 rather than drifting. The handler side is the one
clients already depend on, so this renames the documented parameter and
regenerates the spec.

---------

Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

routers/api/v1/admin/adopt.go

@@ -31,9 +31,9 @@ func ListUnadoptedRepositories(ctx *context.APIContext) {
 	//   in: query
 	//   description: page size of results
 	//   type: integer
-	// - name: pattern
+	// - name: query
 	//   in: query
-	//   description: pattern of repositories to search for
+	//   description: glob pattern of repositories to search for, in the form owner or owner/repo
 	//   type: string
 	// responses:
 	//   "200":

templates/swagger/v1-openapi3.generated.json

@@ -11837,9 +11837,9 @@
             }
           },
           {
-            "description": "pattern of repositories to search for",
+            "description": "glob pattern of repositories to search for, in the form owner or owner/repo",
             "in": "query",
-            "name": "pattern",
+            "name": "query",
             "schema": {
               "type": "string"
             }

templates/swagger/v1-swagger.generated.json

@@ -723,8 +723,8 @@
           },
           {
             "type": "string",
-            "description": "pattern of repositories to search for",
-            "name": "pattern",
+            "description": "glob pattern of repositories to search for, in the form owner or owner/repo",
+            "name": "query",
             "in": "query"
           }
         ],