Fix lief pinning

Author: domdfcoding

.github/workflows/python_ci_linux.yml

@@ -213,7 +213,7 @@ jobs:
           $CONDA/bin/conda config --set always_yes yes --set changeps1 no
           $CONDA/bin/conda update -n base conda
           $CONDA/bin/conda info -a
-          python -m pip install lief=0.14
+          python -m pip install lief==0.14
           $CONDA/bin/conda config --add channels conda-forge
           $CONDA/bin/conda config --add channels domdfcoding