fix(cypress-image): resolve critical security vulnerabilities

[billhimmelsbach]

Let's fix some security vulnerabilities in the old cypress image!

Changes

• updates us to Cypress v15 to resolve a ton of vulnerabilities (the latest Cypress 14 image didn't get us as far)

Before	After

• manually updates two remaining critical vulnerabilities in the crypto/tls and undici libraries that aren't resolved in the latest cypress images. I've added a ticket (GHE [Dockerfile] Update Cypress image version to address crypto/tls and undici vulnerabilities #2711) to remove these overrides someday if Cypress updates their docker image

Before	After

• remove manually installing cypress with the force option, but add legacy peer deps flag because of incompatibility with cypress-keycloak v2.0.2

Testing

1. Do the tests still run and pass locally and in CI?
2. Are the vulnerabilities resolved?

Notes

• There are still some high vulnerabilities we could manually fix in the cypress image, but I'd rather wait to see if they update it or just roll our own version of the cypress image. (See GHE [Dockerfile] Update Cypress image version to address crypto/tls and undici vulnerabilities #2711)

TODO

• update cypress config for v15

Resolves GHE #5478