Odoo Release Updates

[FIX] html_builder, mass_mailing: add defaultImageMimetype config

[FIX] html_builder, html_editor, *: fix scss broken assets dependencies

[FIX] mass_mailing: only display resize option on img-fluid images

[REF] html_editor,web_editor,*: move scss assets from web_editor to html_editor

[IMP] mass_mailing: remove web_editor dependencies

[IMP] google_gmail, miscosoft_outlook: allow using IAP instead of local credentials

[IMP] *: use the "icons fonts" sub-asset-bundle in all asset bundles

[REF] mass_mailing, *: use html Builder instead of OdooEditor

[IMP] mass_mailing: reorganize style files

[IMP] mass_mailing: design option for margin bottom on paragraphs and headings