Add allow_force_push in ProtectedBranch (#1051)

---------
Co-authored-by: Jeremie Bresson <jeremie.bresson@unblu.com>

src/main/java/org/gitlab4j/api/models/ProtectedBranch.java

@@ -13,6 +13,7 @@ public class ProtectedBranch {
     private List<BranchAccessLevel> mergeAccessLevels;
     private List<BranchAccessLevel> unprotectAccessLevels;
     private Boolean codeOwnerApprovalRequired;
+    private Boolean allowForcePush;
 
     public Long getId() {
         return id;
@@ -86,6 +87,19 @@ public class ProtectedBranch {
         return this;
     }
 
+    public Boolean getAllowForcePush() {
+        return allowForcePush;
+    }
+
+    public void setAllowForcePush(Boolean allowForcePush) {
+        this.allowForcePush = allowForcePush;
+    }
+
+    public ProtectedBranch withAllowForcePush(Boolean allowForcePush) {
+        this.allowForcePush = allowForcePush;
+        return this;
+    }
+
     @Override
     public String toString() {
         return (JacksonJson.toJsonString(this));

src/test/resources/org/gitlab4j/api/protected-branch.json

@@ -20,5 +20,7 @@
     {
       "group_id": 2
     }
-  ]
+  ],
+  "allow_force_push": false,
+  "code_owner_approval_required": false
 }