Pass GIT_SSL_NO_VERIFY to git command execution

On some machines we get such an error:

```
npm ERR! git clone https://github.com/hegemonic/taffydb.git Cloning into bare repository '/home/buildfarm/buildAgent3/work/1e02d2bc22f0472a/.npm/_git-remotes/https-github-com-hegemonic-taffydb-git-386cf83c'...
npm ERR! git clone https://github.com/hegemonic/taffydb.git 
npm ERR! git clone https://github.com/hegemonic/taffydb.git fatal: unable to access 'https://github.com/hegemonic/taffydb.git/': server certificate verification failed. CAfile: /etc/ssl/certs/yandex-ca.pem CRLfile: none
```

To fix this we could usually run `git` with `GIT_SSL_NO_VERIFY` env var set to `1`.

```
GIT_SSL_NO_VERIFY=1 git clone https://github.com/hegemonic/taffydb.git
```

So we need an ability to do it with `npm` too, like:

```
GIT_SSL_NO_VERIFY=1 npm install
```

But for now npm do not pass all the `GIT_*` env vars, so this case is only solvable with

```
git config --global http.sslVerify "false"
```

This could help as a workaround, but is not very good as a general solution. Because it sets global config option for git.