[3.14] gh-137090: Remove redundant statement in ``Doc/library/concurrent.interpreters.rst`` (GH-137091) (#137108)

gh-137090: Remove redundant statement in ``Doc/library/concurrent.interpreters.rst`` (GH-137091)
(cherry picked from commit 1e69cd1634e4f0f8c375be85d11925bd12deef23)

Co-authored-by: soolabettu <17737361+soolabettu@users.noreply.github.com>
Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>