Allow Organisations to have a E-Mail (#25082)

Resolves #25057

This adds a E-Mail field to Organisations. The E-Mail is just shown on
the Profile when it is visited by a logged in User. The E-mail is not
used for something else.

**Screenshots:**

![grafik](https://github.com/go-gitea/gitea/assets/15185051/a8d622b3-7278-4c08-984b-9c5ebfdb5471)

![grafik](https://github.com/go-gitea/gitea/assets/15185051/6dcb1dd7-d04b-49eb-bc96-6582cfe9757b)

---------

Co-authored-by: Denys Konovalov <kontakt@denyskon.de>
Co-authored-by: Denys Konovalov <privat@denyskon.de>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: Giteabot <teabot@gitea.io>

templates/swagger/v1_json.tmpl

@@ -17125,6 +17125,10 @@
           "type": "string",
           "x-go-name": "Description"
         },
+        "email": {
+          "type": "string",
+          "x-go-name": "Email"
+        },
         "full_name": {
           "type": "string",
           "x-go-name": "FullName"
@@ -18043,6 +18047,10 @@
           "type": "string",
           "x-go-name": "Description"
         },
+        "email": {
+          "type": "string",
+          "x-go-name": "Email"
+        },
         "full_name": {
           "type": "string",
           "x-go-name": "FullName"
@@ -20100,6 +20108,10 @@
           "type": "string",
           "x-go-name": "Description"
         },
+        "email": {
+          "type": "string",
+          "x-go-name": "Email"
+        },
         "full_name": {
           "type": "string",
           "x-go-name": "FullName"