bump terraform version to newest stable

[michalbagrowski]

infrastructure/Dockerfile

Line 15 in 7c89ddd

ENV TERRAFORM_VERSION 0.12.30

we would like to avoid issue that old terraform will stop support new AWS API.

[michalbagrowski]

aeternity/terraform-aws-aenode-deploy#29
aeternity/terraform-aws-api-gateway#34

[michalbagrowski]

All repositories that use terraform was locked to v2.12.3 so i will proceed with updating each repo by each repo:

1. aeternity/terraform-aws-misc#9
2. aeternity/terraform-aws-testnet#43
3. aeternity/terraform-aws-mainnet#40
4. aeternity/terraform-aws-testnet-api#53
5. aeternity/terraform-aws-mainnet-api#40
6. aeternity/terraform-aws-devnet#27
7. aeternity/terraform-aws-api-loadbalancer#11
8. aeternity/terraform-aws-apps#4
9. aeternity/terraform-aws-aenode-deploy#30
10. aeternity/terraform-aws-api-gateway#35