Add to changelog and add status

Author: atoulme

CHANGELOG.md

@@ -13,6 +13,8 @@ release.
 
 ### Metrics
 
+- Development: Define `remove` operations for synchronous metric instruments. [#4702](https://github.com/open-telemetry/opentelemetry-specification/pulls/4702)
+
 ### Logs
 
 ### Baggage

specification/metrics/api.md

@@ -603,6 +603,7 @@ counterPowerUsed.Add(200, new PowerConsumption { customer = "Jerry" }, ("is_gree
 ```
 
 ##### Remove
+_Status: Development_
 
 Unregister the Counter. It will no longer be reported.
 
@@ -862,6 +863,7 @@ httpServerDuration.Record(100, new HttpRequestAttributes { method = "GET", schem
 ```
 
 ##### Remove
+_Status: Development_
 
 Unregister the Histogram. It will no longer be reported.
 
@@ -979,6 +981,7 @@ backgroundNoiseLevel.record(2.5, roomB);
 ```
 
 ##### Remove
+_Status: Development_
 
 Unregister the Gauge. It will no longer be reported.
 
@@ -1243,6 +1246,7 @@ customersInStore.Add(-1, new Account { Type = "residential" });
 ```
 
 ##### Remove
+_Status: Development_
 
 Unregister the UpDownCounter. It will no longer be reported.