Add default block response to the `default block` block

[mfuhrmeisterDM]

what

We want to be able to set the default response header for the default action if this is set to block.

why

We face the problem that without a default response code some requests are not blocked. Even if AWS says that the default is 403. We solved this by setting the response code manually to 403.

references

• https://docs.aws.amazon.com/waf/latest/developerguide/web-acl-default-action.html

[aknysh]

@mfuhrmeisterDM thank you.

Please run the following commands and commit the changes

make init
make github/init
make readme

[mfuhrmeisterDM]

@mfuhrmeisterDM thank you.

Please run the following commands and commit the changes

make init
make github/init
make readme

done

[aknysh]

/terratest