c47b535bb origin/main org-element: Remove dependency on ‘org-emphasis-regexp-components’

[Ihor Radchenko]

This commit may cause random failures when
org-emphasis-regexp-components is changed by user. org-emph-re is
calculated according to org-emphasis-regexp-components. Changing
org-emphasis-regexp-components can make "(when (looking-at org-emph-re)"
in parsers return nil. The emphasised text will still be fontified, but
not available in the parsed buffer.

Maybe we need to move the logic for org-emph-re from org.el to
org-element.el?

Also, there is org-emphasis-alist. It is even defcustom, but ignored by
org-element.el.

Best,
Ihor