.gitignore files not being applied to created projects

[austinabell]

Seems like with both JS and Rust SDK, the build directories are not being ignored and seems like the gitingore files in the templates are not being added. Doesn't seem like a change has been made wrt this since the last release, and using latest release it still includes build directories like target.

Could do something like ignoring all build directories from the root level, like:

**/target
**/build
**/neardev

or just fixing how the gitignore files are being applied to the generated templates