Fix a typing error in database-types (#3968)

* push should return a ThenableReference

* make thenable only implement then & catch

* Create tame-knives-change.md

* Update .changeset/tame-knives-change.md

Co-authored-by: Sebastian Schmidt <mrschmidt@google.com>

Co-authored-by: Sebastian Schmidt <mrschmidt@google.com>

.changeset/tame-knives-change.md

@@ -0,0 +1,7 @@
+---
+"@firebase/database-types": patch
+"@firebase/database": patch
+"firebase": patch
+---
+
+Updated the type definition for `ThenableReference` to only implement `then` and `catch`, which matches the implementation.

packages/database-types/index.d.ts

@@ -108,7 +108,7 @@ export interface Reference extends Query {
   key: string | null;
   onDisconnect(): OnDisconnect;
   parent: Reference | null;
-  push(value?: any, onComplete?: (a: Error | null) => any): Reference;
+  push(value?: any, onComplete?: (a: Error | null) => any): ThenableReference;
   remove(onComplete?: (a: Error | null) => any): Promise<any>;
   root: Reference;
   set(value: any, onComplete?: (a: Error | null) => any): Promise<any>;
@@ -134,7 +134,9 @@ export interface ServerValue {
   increment(delta: number): Object;
 }
 
-export interface ThenableReference extends Reference, Promise<Reference> {}
+export interface ThenableReference
+  extends Reference,
+    Pick<Promise<Reference>, 'then' | 'catch'> {}
 
 export function enableLogging(
   logger?: boolean | ((a: string) => any),

packages/firebase/index.d.ts

@@ -6902,7 +6902,7 @@ declare namespace firebase.database {
 
   interface ThenableReference
     extends firebase.database.Reference,
-      Promise<Reference> {}
+      Pick<Promise<Reference>, 'then' | 'catch'> {}
 
   /**
    * Logs debugging information to the console.