docs(neptune-alpha): fix typos (#32913)

### Issue # (if applicable)

None

### Reason for this change

Fixed typos in code comments.


### Checklist
- [x] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: andyu17

packages/@aws-cdk/aws-neptune-alpha/lib/cluster.ts

@@ -732,7 +732,7 @@ export class DatabaseCluster extends DatabaseClusterBase implements IDatabaseClu
       throw new Error(`ServerlessScalingConfiguration minCapacity must be greater or equal than 1, received ${serverlessScalingConfiguration.minCapacity}`);
     }
     if (serverlessScalingConfiguration.maxCapacity < 2.5 || serverlessScalingConfiguration.maxCapacity > 128) {
-      throw new Error(`ServerlessScalingConfiguration maxCapacity must be between 2.5 and 128, reveived ${serverlessScalingConfiguration.maxCapacity}`);
+      throw new Error(`ServerlessScalingConfiguration maxCapacity must be between 2.5 and 128, received ${serverlessScalingConfiguration.maxCapacity}`);
     }
     if (serverlessScalingConfiguration.minCapacity >= serverlessScalingConfiguration.maxCapacity) {
       throw new Error(`ServerlessScalingConfiguration minCapacity ${serverlessScalingConfiguration.minCapacity} ` +

packages/@aws-cdk/aws-neptune-alpha/lib/parameter-group.ts

@@ -21,7 +21,7 @@ export class ParameterGroupFamily {
   public static readonly NEPTUNE_1_3 = new ParameterGroupFamily('neptune1.3');
 
   /**
-   * Constructor for specifying a custom parameter group famil
+   * Constructor for specifying a custom parameter group family
    * @param family the family of the parameter group Neptune
    */
   public constructor(public readonly family: string) {}

packages/@aws-cdk/aws-neptune-alpha/test/cluster.test.ts

@@ -835,7 +835,7 @@ describe('DatabaseCluster', () => {
           maxCapacity: 200,
         },
       });
-    }).toThrow(/ServerlessScalingConfiguration maxCapacity must be between 2.5 and 128, reveived 200/);
+    }).toThrow(/ServerlessScalingConfiguration maxCapacity must be between 2.5 and 128, received 200/);
 
     expect(() => {
       new DatabaseCluster(stack, 'Database3', {