Bump coverage from 7.7.0 to 7.7.1 in /testbed (#3289)

Bumps [coverage](https://github.com/nedbat/coveragepy) from 7.7.0 to 7.7.1.
- [Release notes](https://github.com/nedbat/coveragepy/releases)
- [Changelog](https://github.com/nedbat/coveragepy/blob/master/CHANGES.rst)
- [Commits](nedbat/coveragepy@7.7.0...7.7.1)

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

changes/3289.misc.rst

@@ -0,0 +1 @@
+Updated coverage from 7.7.0 to 7.7.1 in /testbed.

testbed/pyproject.toml

@@ -4,7 +4,7 @@ version = "0.0.1"
 
 [project.optional-dependencies]
 test = [
-    "coverage==7.7.0",
+    "coverage==7.7.1",
     "coverage-conditional-plugin == 0.9.0",
     # fonttools is only needed by Android, but we need to use
     # sys.platform == 'linux' as there's no dependency identifier