feat: jira issue importer (#476)

* dev: initialize jira importer

* dev: create service import for jira

* dev: update task to create all users for project and workspace and also create assignees when importing bulk assignees

* dev: create bulk modules import endpoint for jira epics

* dev: create bulk module issues when importing modules

apiserver/plane/db/models/importer.py

@@ -7,7 +7,13 @@ from . import ProjectBaseModel
 
 
 class Importer(ProjectBaseModel):
-    service = models.CharField(max_length=50, choices=(("github", "GitHub"),))
+    service = models.CharField(
+        max_length=50,
+        choices=(
+            ("github", "GitHub"),
+            ("jira", "Jira"),
+        ),
+    )
     status = models.CharField(
         max_length=50,
         choices=(