lexicons: add required `name` field to `repo.create`

Signed-off-by: Seongmin Lee <[e-mail]>

api/tangled/repocreate.go

···
 type RepoCreate_Input struct {
 	// defaultBranch: Default branch to push to
 	DefaultBranch *string `json:"defaultBranch,omitempty" cborgen:"defaultBranch,omitempty"`
+	// name: Name of the repository
+	Name string `json:"name" cborgen:"name"`
 	// rkey: Rkey of the repository record
 	Rkey string `json:"rkey" cborgen:"rkey"`
 	// source: A source URL to clone from, populate this when forking or importing a repository.

lexicons/repo/create.json

···
         "schema": {
           "type": "object",
           "required": [
-            "rkey"
+            "rkey",
+            "name"
           ],
           "properties": {
             "rkey": {
               "type": "string",
               "description": "Rkey of the repository record"
+            },
+            "name": {
+              "type": "string",
+              "description": "Name of the repository"
             },
             "defaultBranch": {
               "type": "string",