dolthub
Warn users about running `dolt sql -q "call dolt_checkout(...);"`
Running dolt sql -q "call dolt_checkout('myBranch');" won't have the effect that customers may initially expect, since dolt sql now runs in its own, separate session each time it's invoked. The checked out branch is changed for that session, but the session ends before any other statements are executed. We've seen a couple users understandably get confused by this.
If we detect that a user is calling dolt sql with a single statement that calls dolt_checkout() we should still execute the statement, but log a warning to make sure they understand that the checked out branch only changed for that individual session that ended when the dolt sql process exited. We should be sure to only show this if a single statement is run though, since it's valid to call dolt_checkout() then include other statements that would operate on that branch, in the same dolt sql -q invocation.
