fix: handle int and float env variable by converting them to string

[vmaerten]

Hey @pd93,

I've tried a solution to fix :

• Regression - env var yaml integer no longer exported to enviroment #1640

It's because since the any vars, some vars are detected as int or float and do not get added to the env map.
So we can let them passthrough and convert them with %v

I've also added a test to convert this case

[andreynering]

Thanks @vmaerten!

I did an additional fix to make booleans work as well: bfc9d78

v3.37.1 will be released soon.