[gitblame] gitblame susceptible to command injection

A command injection vulnerability affects all versions of package gitblame. The injection point is located in line 15 in lib/gitblame.js.

References

• https://nvd.nist.gov/vuln/detail/CVE-2020-28434
• https://security.snyk.io/vuln/SNYK-JS-GITBLAME-1050430
• https://github.com/xjamundx/gitblame/blob/master/lib/gitblame.js#L15
• https://github.com/advisories/GHSA-3486-rvxc-hrrj