Add pytest/pytest-cov support for pre-commit

Pytest (testing framework) and pytest-cov are now part of the python
environment and run automatically by pre-commit hook.

Change-Id: If55cae9f29391c80c809a0487785786a7b9ae62a
Signed-off-by: Diego Russo <diego.russo@arm.com>
diff --git a/Pipfile b/Pipfile
index 33f941f..24e3e5e 100644
--- a/Pipfile
+++ b/Pipfile
@@ -5,6 +5,8 @@
 
 [dev-packages]
 pre-commit = "*"
+pytest = "*"
+pytest-cov = "*"
 ethos-u-vela = {editable = true,path = "."}
 
 [packages]