bugfix: call lspCheckForChanges in more places, such as after a failed merge

[mitchellwrosen]

Overview

Fixes LSP for in-progress merges. I couldn't find a ticket for this issue, but basically, LSP wouldn't properly refresh on merge failure.

Now, it does. I've tested this change manually by setting up the following merge:

LCA

foo = 17
bar = foo + foo

Alice

foo = 18 -- conflicts with bob

Bob

foo = 19 -- conflicts with alice
bar = foo + baz
baz = 200

When merging bob into alice, we end up with a file that looks like

-- alice
foo = 18
-- bob
foo = 19

-- dependents
bar = foo + baz

where baz is in the underlying namespace, because it was an unconflicted add.

Prior to this PR, LSP would complain that baz is out of scope.

[mitchellwrosen]

The CI failures are spurious