Mitigate the temporary loss of docs.scipy.org as an intersphinx target in pipelines.lsst.io and developer.lsst.io builds. Solution is to remove the -W flag to prevent warnings from becoming errors that block merges.

See also: https://community.lsst.org/t/how-docs-scipy-org-and-intersphinx-affect-your-doc-builds/1717?u=jsick