Fix pip install conda error

Error message for `conda`:

    Pip subprocess error:
    ERROR: Ignored the following yanked versions: 3.0.6, 3.5.0, 3.7.0, 3.17.0, 4.0.0, 4.0.1, 4.0.2, 4.0.3, 4.0.4, 4.0.5,
    4.0.7, 4.0.8, 4.0.9, 4.1.2, 4.1.6, 4.2.6, 4.2.7, 4.3.13, 4.3.16
    ERROR: Could not find a version that satisfies the requirement conda==4.9.2 (from versions: none)
    ERROR: No matching distribution found for conda==4.9.2

    failed

    CondaEnvException: Pip failed

Error message for `conda-package-handling`:

    Pip subprocess error:
    ERROR: Could not find a version that satisfies the requirement conda-package-handling==1.7.2 (from versions: 2.1.0, 2.2.0)
    ERROR: No matching distribution found for conda-package-handling==1.7.2

    failed

    CondaEnvException: Pip failed

requirements.txt

@@ -17,8 +17,6 @@ click==7.1.2
 cloudpickle==1.6.0
 colorama==0.4.4
 colorful==0.5.4
-conda==4.9.2
-conda-package-handling==1.7.2
 cryptography==3.3.2
 cycler==0.10.0
 Cython==0.29.21