diagnostic: Declare interFileDependencies = true

`lowering/unused-import` (and `lowering/unused-internal-global` in the
future) both inspect references across the analysis unit, so editing one

file can change the diagnostic set in another. Declaring
`interFileDependencies = false` was incorrect and may cause clients
to skip cross-file refreshes.

Author: aviatesk

src/diagnostic.jl

@@ -1677,7 +1677,7 @@ const DIAGNOSTIC_REGISTRATION_METHOD = "textDocument/diagnostic"
 function diagnostic_options()
     return DiagnosticOptions(;
         identifier = "JETLS/diagnostic",
-        interFileDependencies = false,
+        interFileDependencies = true,
         workspaceDiagnostics = true)
 end