Update Amazon Linux in GHA Workflows

[nirosys]

We currently have Amazon Linux 1 & 2 in our GHA workflows for building and testing ion-c. AL 1 has been EOL since the beginning of the year, and AL 2 has ~1 year left.

AWS has an explanation of the intended lifecycle for Amazon Linux here. We should expect AL2023 to be actively supported until 03-15-2025, at which point it will enter maintenance mode. AL2025 should be expected sometime in early 2025, with a tech preview prior to GA.

GH has changed the GHA runners to default to node20, which is built against a more recent version of glibc than AL1 & AL2 supports. We're able to force the use of node16 for now, until GH completely removes node16 from the image. If we want to keep AL2 in the workflows until it is EOL'd we'll probably need to find a solution for when node16 is completely removed.