Bump version v1.0.0b12 -> v1.0.0b13.

setup.cfg

@@ -1,6 +1,6 @@
 [metadata]
 name = surfaces
-version = 1.0.0b12
+version = 1.0.0b13
 description = Tools for on-surface chemistry, developed at the nanotech@surfaces laboratory, Empa.
 long_description = file: README.md
 long_description_content_type = text/markdown
@@ -47,7 +47,7 @@ per-file-ignores =
     tests/*: U100, U101
 
 [bumpver]
-current_version = "v1.0.0b12"
+current_version = "v1.0.0b13"
 version_pattern = "vMAJOR.MINOR.PATCH[PYTAGNUM]"
 commit_message = "Bump version {old_version} -> {new_version}."
 commit = True