[CHORE] add .chrome_env file to the gitignore (chroma-core#1834)

## Description of changes

*Summarize the changes made by this PR.*
The js tests automatically generate this file so it shouldn't be checked
in.

## Test plan
*How are these changes tested?*

- [x] confirmed that this file is no longer included. 

## Documentation Changes
*Are all docstrings for user-facing APIs updated if required? Do we need
to make documentation changes in the [docs
repository](https://github.com/chroma-core/docs)?*

.gitignore

@@ -35,3 +35,6 @@ terraform.tfstate
 .idea
 
 target/
+
+# environment file generated by the Javascript tests
+.chroma_env