If you're using the build pipeline to install dependencies, you may not need these to be downloaded from their source during each deployment.
If they are being downloaded during every build, you may find that deployments containing a build pipeline are taking a long time to deploy. To help with this, you could cache one or more directories that contain these dependencies to shorten the build time in future deployments.
Some examples of what to add to your build cached files would be:
Please note that these paths may vary, especially if you're running a build command from within a subdirectory.