Adding the nginx config for proxying deploy-previews on appsmith.com domain
This MR fixes changes the following:
1. Cypress tests are now parallelized. Each run is recorded on `https://dashboard.cypress.io` and there are parallel threads spun up in the test phase via `.gitlab-ci.yml`. This cuts the test time down to 16 mins instead of 1 hour. On local systems, the parallelization is turned off.
2. Added nginx configuration for proxying API calls during deploy-previews. Will make reviewing features and code much easier.
Now, there is no need of the `REACT_APP_BASE_URL` field in the `index.js` file. By default all deployments will initiate API calls via `https://<url>/api`. These calls will be proxied by Nginx in non-Netlify scenarios. For deploy previews, you can now visit: `https://<#MR>.appsmith.com` and it should load the code in that branch.
3. For Netlify deployments, made changes to the `netlify.toml` file to redirect the `/api` invocations to the appropriate endpoint. Also modified the build command in "Deploy Settings" in the Netlify console. Check that for details.
4. Now in order to run test cases locally, you will require Nginx & https to work. Check `start-https.sh` for details.
5. Added Docker tags to all master builds which allow us to revert back to previous images in production (if required)
See merge request theappsmith/internal-tools-client!521
c432126db0