Clarify what does wildcard mean in the Metrics SDK View (#2325)

* Clarify what does wildcard mean in the Metrics SDK View

* changelog

* Update specification/metrics/sdk.md

Co-authored-by: Diego Hurtado <ocelotl@users.noreply.github.com>

* feedback

* fix url

Co-authored-by: Diego Hurtado <ocelotl@users.noreply.github.com>
Co-authored-by: Joshua MacDonald <jmacd@users.noreply.github.com>

CHANGELOG.md

@@ -41,6 +41,8 @@ release.
   [#2032](https://github.com/open-telemetry/opentelemetry-specification/pull/2061)
 - Changed default Prometheus Exporter host from `0.0.0.0` to `localhost`.
   ([#2282](https://github.com/open-telemetry/opentelemetry-specification/pull/2282))
+- Clarified wildcard and predicate support in metrics SDK View API.
+  ([#2325](https://github.com/open-telemetry/opentelemetry-specification/pull/2325))
 
 ### Logs
 

specification/metrics/sdk.md

@@ -147,7 +147,10 @@ are the inputs:
 
 * The Instrument selection criteria (required), which covers:
   * The `type` of the Instrument(s) (optional).
-  * The `name` of the Instrument(s), with wildcard support (optional).
+  * The `name` of the Instrument(s). [OpenTelemetry SDK](../overview.md#sdk)
+    authors MAY choose to support wildcard characters, with the question mark
+    (`?`) matching exactly one character and the asterisk character (`*`)
+    matching zero or more characters.
   * The `name` of the Meter (optional).
   * The `version` of the Meter (optional).
   * The `schema_url` of the Meter (optional).