Fix our error count and explain why

codespell_lib/tests/test_basic.py

diff --git a/codespell_lib/tests/test_basic.py b/codespell_lib/tests/test_basic.py
index 524718e..ba7a9fc 100644
--- a/codespell_lib/tests/test_basic.py
+++ b/codespell_lib/tests/test_basic.py
@@ -109,7 +109,8 @@
     assert cs.main("--builtin", "clear,rare,names,informal", fname) == 4
     with fname.open("w") as f:  # overwrite the file
         f.write("var = 'nwe must check codespell likes escapes nin strings'\n")
-    assert cs.main(fname) == 2, "checking our string escape test words are bad"
+    assert cs.main(fname) == 1, "checking our string escape test word is bad"
+    # the first one is missed because the apostrophe means its not currently treated as a word on its own
     with fname.open("w") as f:  # overwrite the file
         f.write("var = '\\nwe must check codespell likes escapes \\nin strings'\n")
     assert cs.main(fname) == 0, "with string escape"