Fix command flag for GCP metrics export (#1763)

* Fix command flag for GCP metrics export

* Additional related fixes for --otel_to_cloud flag

---------

Co-authored-by: Kristopher Overholt <koverholt@google.com>

Author: kumar-dhanagopal

docs/observability/logging.md

@@ -107,10 +107,10 @@ adk web path/to/your/agents_dir
 
 #### GCP export setup
 
-You can enable GCP export using the `-otel_to_cloud` flag:
+You can enable GCP export using the `--otel_to_cloud` flag:
 
 ```bash
-adk web -otel_to_cloud path/to/your/agents_dir
+adk web --otel_to_cloud path/to/your/agents_dir
 ```
 
 ### Python programmatic setup

docs/observability/metrics.md

@@ -51,10 +51,10 @@ adk web path/to/your/agents_dir
 
 #### GCP export
 
-To enable metrics export to Google Cloud Monitoring, use the `-otel_to_cloud` flag:
+To enable metrics export to Google Cloud Monitoring, use the `--otel_to_cloud` flag:
 
 ```bash
-adk web -otel_to_cloud path/to/your/agents_dir
+adk web --otel_to_cloud path/to/your/agents_dir
 ```
 
 ### Programmatic metrics export

docs/observability/traces.md

@@ -50,10 +50,10 @@ adk web path/to/your/agents_dir
 
 #### GCP export
 
-To enable trace export to Google Cloud Trace, use the `-otel_to_cloud` flag:
+To enable trace export to Google Cloud Trace, use the `--otel_to_cloud` flag:
 
 ```bash
-adk web -otel_to_cloud path/to/your/agents_dir
+adk web --otel_to_cloud path/to/your/agents_dir
 ```
 
 ### Programmatic traces export