Fix the external flit lift page link RST syntax

Co-authored-by: chrysle <fritzihab@posteo.de>

Author: webknjaz

source/key_projects.rst

@@ -105,7 +105,7 @@ Python 2, so long as they can be imported on Python 3.
 
 The flit package is lifted by `Matthias Bussonnier
 <https://github.com/Carreau>`__ since October 2023 on the `tidelift platform
-`<https://tidelift.com/lifter/search/pypi/flit`__, and funds sent to the PSF and
+<https://tidelift.com/lifter/search/pypi/flit>`__, and funds sent to the PSF and
 earmarked for PyPA usage.
 
 .. _flit-rationale: https://flit.readthedocs.io/en/latest/rationale.html