UNABLE_TO_GET_ISSUER_CERT_LOCALLY error when running – webdriver-manager start through npm

I am trying to integrate protractor test cases in jenkins. However I am getting UNABLE_TO_GET_ISSUER_CERT_LOCALLY.

I have tried the following

RUN npm install -g protractor
RUN webdriver-manager clean # remove the downloaded driver files
#RUN webdriver-manager update --ignore_ssl # bypass network proxy
RUN webdriver-manager update --versions.chrome 2.24 --ignore_ssl=true
RUN webdriver-manager version # 12.0.6
RUN webdriver-manager start --ignore_ssl=true
RUN (cd protractorTests and protractor conf.js)

When i am on company network i get this error. However i cant go off network when i am running these commands in jenkins.

{ Error: unable to get local issuer certificate
    at TLSSocket.<anonymous> (_tls_wrap.js:1116:38)
    at emitNone (events.js:106:13)
    at TLSSocket.emit (events.js:208:7)
    at TLSSocket._finishInit (_tls_wrap.js:643:8)
    at TLSWrap.ssl.onhandshakedone (_tls_wrap.js:473:38) code: 'UNABLE_TO_GET_ISSUER_CERT_LOCALLY' }

Source: StackOverflow