[CLI-122] throw an error for delete commands if item doesn't exit

[bright-poku]

Description

This PR allows the delete commands for apis, apps and rules to return an error if item doesn't exit
as shown below

References

https://auth0team.atlassian.net/browse/CLI-122

Testing

Describe how this can be tested by reviewers. Be specific about anything not tested and reasons why. If this library has unit and/or integration testing, tests should be added for new functionality and existing tests should complete without errors.

Please include any manual steps for testing end-to-end or functionality not covered by unit/integration tests.

Also include details of the environment this PR was developed in (language/platform/browser version).

• This change adds test coverage for new/changed/fixed functionality

Checklist

• I have added documentation for new/changed functionality in this PR or in auth0.com/docs
• All active GitHub checks for tests, formatting, and security are passing
• [X ] The correct base branch is being used, if not master

[Widcket]

Let's reuse the same spinner, like so:

	return ansi.Spinner("Deleting Application", func() error {
		_, err := cli.api.Client.Read(inputs.ID)

		if err != nil {
			return fmt.Errorf("Unable to delete application. The specified Id: %v doesn't exist", inputs.ID)
		}

		return cli.api.Client.Delete(inputs.ID)
	})

[bright-poku]

Let's reuse the same spinner, like so:

	return ansi.Spinner("Deleting Application", func() error {
		_, err := cli.api.Client.Read(inputs.ID)

		if err != nil {
			return fmt.Errorf("Unable to delete application. The specified Id: %v doesn't exist", inputs.ID)
		}

		return cli.api.Client.Delete(inputs.ID)
	})

@Widcket thanks. I made the changes

[Widcket]

Thanks!