[FIX] web: Aria attributes on buttons Export All & optional columns

Some aria attributes were missing or incorrectly set on these new
buttons:
- The button "Export All" was missing an `aria-label` attribute
- The button to show/hide optional columns was also missing an
  `aria-label` attribute, and its menu items (checkboxes to show/hide
  columns) were missing a proper role
- Ever since the debug manager was added in frontend on 73327db0,
  the `aria-label` attribute was not being rendered correctly on the
  button to open developer tools

closes odoo/odoo#70390

X-original-commit: 620e4cc2
Signed-off-by: Nicolas Lempereur (nle) <nle@odoo.com>