Enable pandas plotting unit tests for cudf.pandas (#15547)

Locally, these tests ran without any crashed workers/hangs

closes #15428

Authors:
  - Matthew Roeschke (https://github.com/mroeschke)
  - GALI PREM SAGAR (https://github.com/galipremsagar)

Approvers:
  - Vyas Ramasubramani (https://github.com/vyasr)
  - GALI PREM SAGAR (https://github.com/galipremsagar)

URL: #15547

python/cudf/cudf/pandas/scripts/run-pandas-tests.sh

@@ -22,8 +22,7 @@ set -euo pipefail
 # of Pandas installed.
 PANDAS_VERSION=$(python -c "import pandas; print(pandas.__version__)")
 
-PYTEST_IGNORES="--ignore=tests/plotting \
---ignore=tests/tslibs/test_parsing.py \
+PYTEST_IGNORES="--ignore=tests/tslibs/test_parsing.py \
 --ignore=tests/io/parser/common/test_read_errors.py"
 
 mkdir -p pandas-testing