add word_break dynamic approach up -> down. (#8039)

* add word_break dynamic approach up -> down.

* updating DIRECTORY.md

* Update word_break.py

fix review notes.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Update word_break.py

fix review notes

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* fix review notes

* add trie type

* Update word_break.py

add typing Any to trie.

* Update dynamic_programming/word_break.py

Co-authored-by: Caeden Perelli-Harris <caedenperelliharris@gmail.com>

* Update dynamic_programming/word_break.py

Co-authored-by: Christian Clauss <cclauss@me.com>

* Update dynamic_programming/word_break.py

Co-authored-by: Christian Clauss <cclauss@me.com>

* Update dynamic_programming/word_break.py

Co-authored-by: Christian Clauss <cclauss@me.com>

* Update dynamic_programming/word_break.py

Co-authored-by: Christian Clauss <cclauss@me.com>

* fix review notes

Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Caeden Perelli-Harris <caedenperelliharris@gmail.com>
Co-authored-by: Christian Clauss <cclauss@me.com>