update testnet host

[Patel-Raj11]

High Level Overview of Change

testnet host was changed from s.altnet.rippletest.net to s1.altnet.rippletest.net

Context of Change

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Refactor (non-breaking change that only restructures code)
• Tests (You added tests for code that already exists, or your new feature included in this PR)
• Documentation Updates
• Release

Before / After

Test Plan

Added test

[Patel-Raj11]

Since, it's not a major issuer on Testnet, moving this PR to draft state until https://s.altnet.rippletest.net:51235/crawl starts responding again.