[MM-31790] Support Packet Generation BACKEND (#16667)

* init commit

* clean up the code

* make mocks

* fix translations

* mocks and lint fixes

* add tests

* little fixes

* Update i18n/en.json

Co-authored-by: Scott Bishel <scott.bishel@mattermost.com>

* Update i18n/en.json

Co-authored-by: Scott Bishel <scott.bishel@mattermost.com>

* Update i18n/en.json

Co-authored-by: Scott Bishel <scott.bishel@mattermost.com>

* Update i18n/en.json

Co-authored-by: Scott Bishel <scott.bishel@mattermost.com>

* Update i18n/en.json

Co-authored-by: Scott Bishel <scott.bishel@mattermost.com>

* Address Comments

* fix i18n

* update api endpoint

* add enable file and file level for conditional show of banner

* Address Comments

* Make it more clear about returns

* Create zip file utility function

* update en.json

* address comments

* write tests

* check for data in test

* remove warning string

* Correct expected and actual

* set database through environment variables

* reset environment variable at end of test

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>
Co-authored-by: Scott Bishel <scott.bishel@mattermost.com>

model/client4.go

@@ -3278,6 +3278,21 @@ func (c *Client4) GetFileInfosForPost(postId string, etag string) ([]*FileInfo,
 
 // General/System Section
 
+// GenerateSupportPacket downloads the generated support packet
+func (c *Client4) GenerateSupportPacket() ([]byte, *Response) {
+	r, appErr := c.DoApiGet(c.GetSystemRoute()+"/support_packet", "")
+	if appErr != nil {
+		return nil, BuildErrorResponse(r, appErr)
+	}
+	defer closeBody(r)
+
+	data, err := ioutil.ReadAll(r.Body)
+	if err != nil {
+		return nil, BuildErrorResponse(r, NewAppError("GetFile", "model.client.read_job_result_file.app_error", nil, err.Error(), r.StatusCode))
+	}
+	return data, BuildResponse(r)
+}
+
 // GetPing will return ok if the running goRoutines are below the threshold and unhealthy for above.
 func (c *Client4) GetPing() (string, *Response) {
 	r, err := c.DoApiGet(c.GetSystemRoute()+"/ping", "")