ci: fix webgl e2e test failures (only on CI) (#1296)

* ci: update executor and browser flag for circleci orbs

* ci: browser flag when running percy/ci tests

* ci: limit ourselves to the executors defined by the cypress orb for now

.circleci/config.yml

@@ -317,6 +317,8 @@ workflows:
       # E2E: PWA
       - cypress/run:
           name: 'E2E: PWA'
+          executor: cypress/browsers-chrome76
+          browser: chrome
           pre-steps:
             - run: 'rm -rf ~/.yarn && npm i -g yarn && yarn -v && yarn global
                 add wait-on' # Use yarn latest
@@ -339,6 +341,8 @@ workflows:
       # E2E: script-tag
       - cypress/run:
           name: 'E2E: Script Tag'
+          executor: cypress/browsers-chrome76
+          browser: chrome
           pre-steps:
             - run: 'rm -rf ~/.yarn && npm i -g yarn && yarn -v && yarn global
                 add wait-on' # Use yarn latest
@@ -367,6 +371,8 @@ workflows:
       # Update hub.docker.org
       - cypress/run:
           name: 'Generate Percy Snapshots'
+          executor: cypress/browsers-chrome76
+          browser: chrome
           pre-steps:
             - run: 'rm -rf ~/.yarn && npm i -g yarn && yarn -v && yarn global
                 add wait-on' # Use yarn latest
@@ -442,6 +448,8 @@ workflows:
       # and record a Cypress dashboard test run
       - cypress/run:
           name: 'Generate Percy Snapshots'
+          executor: cypress/browsers-chrome76
+          browser: chrome
           pre-steps:
             - run: 'rm -rf ~/.yarn && npm i -g yarn && yarn -v && yarn global
                 add wait-on' # Use yarn latest