fix: change BuildVersion to int64 allowing larger build numbers

[asserh]

Checklist

• I've read and followed the Contribution Guidelines
• step.yml and README.md is updated with the changes (if needed)

Version

Requires a patch version.

Context

Changes build_version to an int64, allowing larger numbers to be used as the build number.

#36

Changes

BuildVersion is now int64 (instead of an int)

Investigation details

This was not an issue on previous versions, our builds started failing once 2.0 was released. Might be others affected that use similar format for their builds

[tothszabi]

Hey @asserh thanks for the PR. I have made some fixes in the meantime and merged master into your fork. But unfortunately this means that could you update one more thing in your PR?

In the step/step.go file on line 141 I had to add another int -> string conversion and could you update that as well just like you did for the others?

Now because of this the CI is failing and I cannot merge your PR.

[asserh]

Gotcha! I pushed a commit that fixes that line. Now it also converts from int64. I just pushed the fix on top, let me know if you need me to rebase to include it in the original commit. Perhaps you squash PR:s anyway when merging?

[ofalvai]

Looks good to me now @asserh, thank you for the contribution! 💯
Yes, we do squash merges, it's all good from now on