Go and PHP language versions

Is there an existing issue for this?

[X] I have searched the existing issues

Describe the bug

There are a couple of languages with issues when trying to set the language version.

Go

Docs and code indicate Go should only work with versions 17 and 18, and that 17 should be the default.

Testing shows otherwise, with only 1.18 and 1.19 being available and 1.19 being the default:

If version is set to 1.17 in go.mod, the app is built with Go 1.19.4.
If version is set to 1.18 in go.mod, the the app is built as expected with Go 1.18.
If version is set to 1.19 in go.mod, the the app is built as expected with Go 1.19.

PHP

Docs indicate PHP should only work with 8.0, 8.1, and 8.2; with 8.2 as the default. Code seems to indicate the available versions are: 7.4, 8.0, 8.1, and 8.2; with 8.2 as the default.

Testing shows otherwise, with 7.4 deprecated and 8.1 being the default:

If a composer.json file is NOT present in the repo, Nixpacks should use the default PHP version, but the app is built with PHP version 8.1.13.
If version is set to 7.4 in composer.json, the build fails and the build log shows this error: “php74 has been dropped due to the lack of maintanence from upstream for future releases.” While this is to be expected due to the deprecation of that version, the code referenced above includes PHP 7.4.
If version is set to 8.0, 8.1, or 8.2, the app is built as expected with the specified language version.

To reproduce

Create applications with each of the languages and versions described, then check the version of the language used.

Expected behavior

Expected documentation and Nixpacks code to agree.

Environment

Tested on Railway.

railwayapp / nixpacks