docs(lambda): Fixed consecutive "when" (#20761)

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packages/@aws-cdk/aws-lambda/lib/function.ts

@@ -354,7 +354,7 @@ export interface FunctionProps extends FunctionOptions {
    * For valid values, see the Runtime property in the AWS Lambda Developer
    * Guide.
    *
-   * Use `Runtime.FROM_IMAGE` when when defining a function from a Docker image.
+   * Use `Runtime.FROM_IMAGE` when defining a function from a Docker image.
    */
   readonly runtime: Runtime;
 
@@ -1298,4 +1298,4 @@ export class FunctionVersionUpgrade implements IAspect {
       cfnFunction.addPropertyOverride('Description', `${desc}version-hash:${calculateFunctionHash(node)}`);
     }
   };
-}
+}