Ignore node_modules when generate project with bsb

[wingyplus]

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• Is it a bug? Usage questions should often be asked in the forum instead.
• Concise, focused, friendly issue title & description.
• A minimal, reproducible example.
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bsb version (bsb -v): 8.3.1

Currently, if we generate project with bsb -init. The generated project will generate gitignore but it doesn't have node_module in the list. Here is my reproduce step:

$ bsb -init rescript-test -theme basic
Making directory rescript-test
$ ls -la rescript-test
total 32
drwxr-xr-x   7 thanabodee  staff   224 Oct 21 14:56 ./
drwxr-xr-x  62 thanabodee  staff  1984 Oct 21 14:56 ../
-rw-r--r--   1 thanabodee  staff   178 Oct 21 14:56 .gitignore
-rw-r--r--   1 thanabodee  staff    65 Oct 21 14:56 README.md
-rw-r--r--   1 thanabodee  staff   154 Oct 21 14:56 bsconfig.json
-rw-r--r--   1 thanabodee  staff   302 Oct 21 14:56 package.json
drwxr-xr-x   3 thanabodee  staff    96 Oct 21 14:56 src/
$ cat ./rescript-test/.gitignore
*.exe
*.obj
*.out
*.compile
*.native
*.byte
*.cmo
*.annot
*.cmi
*.cmx
*.cmt
*.cmti
*.cma
*.a
*.cmxa
*.obj
*~
*.annot
*.cmj
*.bak
lib/bs
*.mlast
*.mliast
.vscode
.merlin
.bsb.lock