Replace dep @types/blob-util (it's deprecated)

[jennifer-shehane]

Current behavior:

We include @types/blob-util as a dep in the cli here: https://github.com/cypress-io/cypress/blob/v4.0-release/cli/package.json#L64:L64

As mentioned in this PR #5684 (review), this dep has been deprecated since blob-util provides it's own types in their package as mentioned here: https://www.npmjs.com/package/%40types/blob-util

Desired behavior:

Replace use of @types/blob-util to include the types correctly.

Versions

3.8.0

[sainthkh]

After some research, I learned that updating blob-util is a breaking change.

In 1.3.3, the return type of blob-util functions are Promise. But from 2.0.0, they're Blob object. That's why attempting to fix them in #5780 failed.

1.3.0 of blob-util doesn't use TypeScript and @types/blob-util@1.3.3 is not deprecated.

For now, we should use @types/blob-util@1.3.3 and update it to 2.0.2 and remove @types/blob-util at Cypress 4.0.