SSL issues w/ Zscaler when running setup.sh

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=>ERROR [inferno 10/12] RUN gem install bundler 1.7s
[inferno 10/12] RUN gem install bundler:
1.027 ERROR: SSL verification error at depth 2: unable to get local issuer certificate (20)
1.027 ERROR: You must add /C=US/ST=California/L=San Jose/O=Zscaler Inc./OU=Zscaler Inc./CN=Zscaler Root CA/emailAddress=[email protected] to your local trusted store
1.179 ERROR: SSL verification error at depth 2: unable to get local issuer certificate (20)
1.179 ERROR: You must add /C=US/ST=California/L=San Jose/O=Zscaler Inc./OU=Zscaler Inc./CN=Zscaler Root CA/emailAddress=[email protected] to your local trusted store
1.319 ERROR: SSL verification error at depth 2: unable to get local issuer certificate (20)
1.319 ERROR: You must add /C=US/ST=California/L=San Jose/O=Zscaler Inc./OU=Zscaler Inc./CN=Zscaler Root CA/emailAddress=[email protected] to your local trusted store
1.322 ERROR: Could not find a valid gem 'bundler' (>= 0), here is why:
1.322 Unable to download data from https://rubygems.org/ - SSL_connect returned=1 errno=0 peeraddr=151.101.1.227:443 state=error: certificate verify failed (unable to get local issuer certificate) (https://rubygems.org/specs.4.8.gz)
1.470 ERROR: SSL verification error at depth 2: unable to get local issuer certificate (20)
1.470 ERROR: You must add /C=US/ST=California/L=San Jose/O=Zscaler Inc./OU=Zscaler Inc./CN=Zscaler Root CA/emailAddress=[email protected] to your local trusted store
[+] Building 0/2L verification error at depth 2: unable to get local issuer certificate (20)
⠹ Service inferno Building 4.2s
⠹ Service worker Building 4.2s
failed to solve: process "/bin/sh -c gem install bundler" did not complete successfully: exit code: 2

Hi there. I'm having some issues getting the setup script kicked off, likely due to my company using Zscaler.
In my local terminal, I can run something like "gem install bundler" just fine. However when it comes to the Docker container, we run into issues. I've scoured the web and tried all sorts of things involving my ZScaler Root CA pem file. But no luck. I have very limited experience with Docker, and even less with things like Ruby, so any help in resolving this would be greatly appreciated.