breaking: Update all execution role related variables

[marlonparmentier]

This update consists of 2 parts:

(1) Update and rename the role_arn variable to object execution_role_custom.arn to allow proper usage of count.

This update in variable structure is to overcome the error below when supplying your own role_arn in the previous version. Breaking change for people that are using the role_arn.

The "count" value depends on resource attributes that cannot be determined until apply, so Terraform cannot predict how many instances will be created. To work around this, use the -target
argument to first apply only the resources that the count depends on.

(2) Update all other variables related to configuring the modules built in lambda execution role.

See the upgrading guide. A new variable execution_role has been introduced which contains all variables related to configuring the lambda execution role.

[github-actions]

Terraform Format and Style 🖌success

Terraform Initialization ⚙️``

Terraform Lint 📖success

Terraform Validation 🤖success

Validation Output

Success! The configuration is valid.

[marwinbaumannsbp]

Could you update the UPGRADING.md?

[marlonparmentier]

LGTM