Feat: parse email (#10181)

### What problem does this PR solve?

- Dataflow support email.
- Fix old email parser.
- Add new depends to parse msg file.

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)
- [x] New Feature (non-breaking change which adds functionality)
- [x] Other (please describe): add new depends.

rag/flow/tests/dsl_examples/general_pdf_all.json

@@ -89,6 +89,22 @@
                   "lang": "Chinese",
                   "llm_id": "SenseVoiceSmall",
                   "output_format": "json"
+                },
+                "email": {
+                  "suffix": [
+                    "msg"
+                  ],
+                  "fields": [
+                    "from",
+                    "to",
+                    "cc",
+                    "bcc",
+                    "date",
+                    "subject",
+                    "body",
+                    "attachments"
+                  ],
+                  "output_format": "json"
                 }
               }
           }