Updated template to use dynamic resolution of SSM parameter store value

[dms1981]

This PR resolves #1385 in the Modernisation Platform repository.

This PR replaces the data call which can result in outdated AMI versions being used in templates, for a public SSM Parameter resolve statement which will return the value from the parameter when instances are created, ensuring that the latest version is used.

[github-actions]

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Setting default tflint config...
Running tflint --init...
Installing "terraform" plugin...
Installed "terraform" (source: github.com/terraform-linters/tflint-ruleset-terraform, version: 0.9.1)
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[mikereiddigital]

lg2m