Description

Resolves SI-1817

Fixes the issue, when it is not possible to stake if some incorrect ref is provided.

Testing notes

The logic of processing the provided ref address looks like this:

1. if the ref is an Ethereum address (0x...), then the ref is used as is
2. if the ref starts with 'http[s]://', then the ref is replaced with a fallback address
3. if the ref ends with 'lido.fi', then the ref is replaced with a fallback address
   It is possible to pass ENS names as a ref. We assume that no one uses 'lido.fi' ENS name, because not all ENS names end with '.eth' and it is technically possible to have 'lido.fi' ENS name.
4. only in the end, after all other checks, we are trying to get ENS name using the provided ref. Because this request takes some time (5 seconds or so).

Checked with refs:

• ?ref=blog.lido.fi – no ENS request, ignoring the ref
• /?ref=https://test – no ENS request, ignoring the ref
• ?ref=test.com – we have to do a ENS request, because it is a possible ENS name. If the name is not resolved – ignore, return fallback.

Checklist:

• Checked the changes locally.
• Created / updated analytics events.
• Created / updated the technical documentation (README.md / docs / etc.).
• Affects / requires changes in other services (Matomo / Sentry / CloudFlare / etc.).