remove pytest-cov build dependency

Simplify the build process by removing the code coverage library.

This makes it easier to package portend for EPEL 9. pytest-cov requires
python-pytest-xdist -> python-gevent -> libuv-devel and libev-devel,
and those two -devel packages are not available in the RHEL 9 composes.

python-portend.spec

@@ -23,7 +23,6 @@ Summary:        portend documentation
 BuildRequires:  python3-devel
 BuildRequires:  python3dist(jaraco.functools)
 BuildRequires:  python3dist(pytest) >= 3.4
-BuildRequires:  python3dist(pytest-cov)
 #BuildRequires:  python3dist(pytest-sugar) >= 0.9.1
 BuildRequires:  python3dist(setuptools)
 BuildRequires:  python3dist(setuptools-scm) >= 1.15
@@ -58,6 +57,10 @@ sed -i '/^addopts=--flake8$/d' pyproject.toml
 sed -i '/pytest-flake8/d' setup.cfg
 rm .flake8
 
+# skip test coverage metrics
+sed -i '/^addopts = "--cov"$/d' pyproject.toml
+sed -i '/pytest-cov/d' setup.cfg
+
 %build
 %py3_build