[ci] Use pip through Python
Avoid using an old "pip3" wrapper script, as indicated by this warning
we're getting in CI:
```
WARNING: pip is being invoked by an old script wrapper. This will fail in a future version of pip.
Please see https://github.com/pypa/pip/issues/5599 for advice on fixing the underlying issue.
To avoid this problem you can invoke Python with '-m pip' instead of running pip directly.
```
Signed-off-by: Philipp Wagner <phw@lowrisc.org>
diff --git a/ci/install-package-dependencies.yml b/ci/install-package-dependencies.yml
index fa5f866..ced53f0 100644
--- a/ci/install-package-dependencies.yml
+++ b/ci/install-package-dependencies.yml
@@ -67,7 +67,7 @@
# specify that an older version of a package must be used for a certain
# Python version. If that information is not read, pip installs the latest
# version, which then fails to run.
- pip3 install --user -U pip six
+ python3 -m pip install --user -U pip six
# There's been a bit of a kerfuffle about setuptools version 50, which
# breaks importing distutils on Debian/Ubuntu systems. Make sure we don't
