[BUG] Update connection wording in docs

[PiVortex]

Description

Here its called nearConnection
https://docs.near.org/tools/near-api#connect
Here its called connection
https://docs.near.org/tools/near-api#instantiate-account

Page URL

https://docs.near.org/tools/near-api

Impact

• Incorrect information
• Missing information
• Unclear explanation
• Broken link
• Code example doesn't work
• Other (please specify in description)

Suggested Fix

Update all to nearConnection. Check all examples here to make sure the same https://github.com/near-examples/near-api-examples/tree/main/javascript

[bucanero]

seems similiar to #1926 🤔