style(post): left aligned menu below button css change to overflow-y: auto

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left aligned menu below button css change to overflow-y: auto toc_button.ejs line:31

- <ul class="post-toc-wrap mdl-menu mdl-menu--bottom-left mdl-js-menu mdl-js-ripple-effect" for="post-toc-trigger-btn" style="max-height:80vh; overflow-y:scroll;">
+ <ul class="post-toc-wrap mdl-menu mdl-menu--bottom-left mdl-js-menu mdl-js-ripple-effect" for="post-toc-trigger-btn" style="max-height:80vh; overflow-y:auto;">