Add "dialogs" to US dictionary

[DimitriPapadopoulos]

The current aspell dictionary contains singular "dialog", as well as "dialogue"/"dialogues". Only the plural "dialogs" is missing.

• Oxford Learner's
• Cambridge
• Collins
• Merriam-Webster

From the Google Books Ngram database:

• https://books.google.com/ngrams/graph?content=dialog%2Cdialogs%2Cdialogue%2Cdialogues&year_start=1800&year_end=2019&corpus=en-2019
• http://app.aspell.net/lookup-freq?words=dialog%0D%0Adialogs%0D%0Adialogue%0D%0Adialogues;also=similar;parm=full