Table tweaks

[max-nextcloud]

Some of these were originally posted by @juliushaertl in #2235 (comment) and by @max-nextcloud in #2235 (comment)

In order of priority:

• make text after a table start below - not next to it on the right Fix/2267 table tweaks #2289
• hide table editing buttons in read only editor Fix/2267 table tweaks #2289
• check if rows and columns can be added / removed and disable buttons accordingly
• refactor test layout, put all tables fixtures in one folder
• accessibility for adding columns and rows (currently tab moves past the buttons in the cells)
• drop colspan=1, rowspan=1, etc from rendered html - first attempt at this failed.
• Tables don't support right justified columns #3304 (allow left, right and center align of columns)
• Improve table navigation with keyboard #2266

[luka-nextcloud]

@max-nextcloud

refactor test layout, put all tables fixtures in one folder

I don't really understand this point. Currently, the table fixtures is only one file cypress/fixtures/Table.md. Do you mean to split this file into many smaller files and put them into a folder?

drop colspan=1, rowspan=1, etc from rendered html - first attempt at this failed.

I don't really understand this point.