Add Trusted Types support for script injection

[russellsteadman]

Trusted Types

Trusted Types is a new web API to support script security, and it can be used as part of a Content-Security-Policy.

Problem

The recaptcha script injection would be blocked if require-trusted-types-for 'script' is added to the CSP, and there is no current workaround.

Fixes

• An optional trustedTypePolicy prop was added, so when Trusted Types is supported by the browser and the prop is provided, the policy is applied.
• Dependencies were updated
• Version was bumped to v0.3.0 for release