Moved from Dep to Go Modules

We have finally dropped go dep and moved over to go mod !

During the move, some dependencies have been bumped.

vendor/github.com/google/go-github/github/issues_events.go

@@ -34,9 +34,13 @@ type IssueEvent struct {
 	//       The Actor committed to master a commit mentioning the issue in its commit message.
 	//       CommitID holds the SHA1 of the commit.
 	//
-	//     reopened, locked, unlocked
+	//     reopened, unlocked
 	//       The Actor did that to the issue.
 	//
+	//     locked
+	//       The Actor locked the issue.
+	//       LockReason holds the reason of locking the issue (if provided while locking).
+	//
 	//     renamed
 	//       The Actor changed the issue title from Rename.From to Rename.To.
 	//
@@ -64,12 +68,13 @@ type IssueEvent struct {
 	Issue     *Issue     `json:"issue,omitempty"`
 
 	// Only present on certain events; see above.
-	Assignee  *User      `json:"assignee,omitempty"`
-	Assigner  *User      `json:"assigner,omitempty"`
-	CommitID  *string    `json:"commit_id,omitempty"`
-	Milestone *Milestone `json:"milestone,omitempty"`
-	Label     *Label     `json:"label,omitempty"`
-	Rename    *Rename    `json:"rename,omitempty"`
+	Assignee   *User      `json:"assignee,omitempty"`
+	Assigner   *User      `json:"assigner,omitempty"`
+	CommitID   *string    `json:"commit_id,omitempty"`
+	Milestone  *Milestone `json:"milestone,omitempty"`
+	Label      *Label     `json:"label,omitempty"`
+	Rename     *Rename    `json:"rename,omitempty"`
+	LockReason *string    `json:"lock_reason,omitempty"`
 }
 
 // ListIssueEvents lists events for the specified issue.
@@ -87,6 +92,8 @@ func (s *IssuesService) ListIssueEvents(ctx context.Context, owner, repo string,
 		return nil, nil, err
 	}
 
+	req.Header.Set("Accept", mediaTypeLockReasonPreview)
+
 	var events []*IssueEvent
 	resp, err := s.client.Do(ctx, req, &events)
 	if err != nil {