fix: change model provider name issue Ref #8691 (#8710)

api/core/model_runtime/model_providers/jina/jina.yaml

@@ -1,4 +1,4 @@
-provider: Jina AI
+provider: jina
 label:
   en_US: Jina AI
 description:

api/core/tools/provider/builtin/jina/jina.yaml

@@ -1,6 +1,6 @@
 identity:
   author: Dify
-  name: Jina AI
+  name: jina
   label:
     en_US: Jina AI
     zh_Hans: Jina AI