[3.13] gh-121746: Bind Alt+Enter to "accept" in the REPL (GH-121754) (GH-121803)

(cherry picked from commit 6522f0e438a8c56a8f3cce2095b193ea6e3f5016)

Co-authored-by: Rodrigo Girão Serrão <5621605+rodrigogiraoserrao@users.noreply.github.com>