fix(tools/alloydbgetinstance): remove parameter duplication (#1993)

## Description

Previous merge conflict caused parameter duplications

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🛠️ Fixes https://github.com/gemini-cli-extensions/alloydb/issues/97

internal/tools/alloydb/alloydbgetinstance/alloydbgetinstance.go

@@ -84,9 +84,6 @@ func (cfg Config) Initialize(srcs map[string]sources.Source) (tools.Tool, error)
 		parameters.NewStringParameter("location", "The location of the instance (e.g., 'us-central1')."),
 		parameters.NewStringParameter("cluster", "The ID of the cluster."),
 		parameters.NewStringParameter("instance", "The ID of the instance."),
-		parameters.NewStringParameter("location", "The location of the instance (e.g., 'us-central1')."),
-		parameters.NewStringParameter("cluster", "The ID of the cluster."),
-		parameters.NewStringParameter("instance", "The ID of the instance."),
 	}
 	paramManifest := allParameters.Manifest()