test(go): add cases for newlines de-indentation

test(go): combine new indent test cases

test(go): add incorrect indent after var closing )

this case does not work correctly already so add that in since this PR
does not address that case

test(go): set current lines in indent test

test(go): simplify test case

tests/indent/go/issue-2369-newline.go

@@ -0,0 +1,8 @@
+// https://github.com/nvim-treesitter/nvim-treesitter/issues/2369
+package main
+
+import "fmt"
+
+func new_line() {
+	fmt.Println("Hello, World!")
+}