docs: Fix typo in comment (#1408)

Fix typo in comment.

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Co-authored-by: Richard Levasseur <richardlev@gmail.com>
Co-authored-by: Richard Levasseur <rlevasseur@google.com>

python/private/coverage_deps.bzl

diff --git a/python/private/coverage_deps.bzl b/python/private/coverage_deps.bzl
index 863d496..7980779 100644
--- a/python/private/coverage_deps.bzl
+++ b/python/private/coverage_deps.bzl
@@ -99,7 +99,7 @@
 _coverage_patch = Label("//python/private:coverage.patch")
 
 def coverage_dep(name, python_version, platform, visibility):
-    """Register a singe coverage dependency based on the python version and platform.
+    """Register a single coverage dependency based on the python version and platform.
 
     Args:
         name: The name of the registered repository.