Namaster libchealpix installation issue

[felipeaoli]

investigate the namaster problem in the installation:

      configure: error: could not find the cfitsio library
      ERROR: failed to configure HEALPix. Check CFITSIO is installed and reachable.
      error: Failed to install libchealpix.
      [end of output]

  note: This error originates from a subprocess, and is likely not a problem with pip.
error: legacy-install-failure

× Encountered error while trying to install package.
╰─> pymaster