Move 'sur' typo from rare to code

Closes #2299
diff --git a/codespell_lib/data/dictionary_code.txt b/codespell_lib/data/dictionary_code.txt
index 2e8b266..59e7fb0 100644
--- a/codespell_lib/data/dictionary_code.txt
+++ b/codespell_lib/data/dictionary_code.txt
@@ -55,6 +55,7 @@
 stringly->strongly, stringy,
 subpatchs->subpatches
 subprocess'->subprocess's
+sur->sure, sir,
 tarceback->traceback
 tarcebacks->tracebacks
 templace->template
diff --git a/codespell_lib/data/dictionary_rare.txt b/codespell_lib/data/dictionary_rare.txt
index ba88768..0a6f53a 100644
--- a/codespell_lib/data/dictionary_rare.txt
+++ b/codespell_lib/data/dictionary_rare.txt
@@ -163,7 +163,6 @@
 straightaway->straight away
 straighted->straightened, straighten,
 suppressable->suppressible
-sur->sure, sir,
 therefor->therefore
 therefrom->there from
 theses->these, thesis,