Add db metric name to semantic conventions (#3115)

Author: shalevr

CHANGELOG.md

@@ -9,6 +9,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Adds environment variables for log exporter
   ([#3037](https://github.com/open-telemetry/opentelemetry-python/pull/3037))
 
+- Add db metric name to semantic conventions
+  ([#3115](https://github.com/open-telemetry/opentelemetry-python/pull/3115))
+
 ## Version 1.15.0/0.36b0 (2022-12-09)
 
 - Regenerate opentelemetry-proto to be compatible with protobuf 3 and 4

opentelemetry-semantic-conventions/src/opentelemetry/semconv/metrics/__init__.py

@@ -30,3 +30,5 @@ class MetricInstruments:
     HTTP_CLIENT_REQUEST_SIZE = "http.client.request.size"
 
     HTTP_CLIENT_RESPONSE_SIZE = "http.client.response.size"
+
+    DB_CLIENT_CONNECTIONS_USAGE = "db.client.connections.usage"