docs: fix typos (#20394)

Co-authored-by: Raphael <glephunter@gmail.com>
Co-authored-by: smjonas <jonas.strittmatter@gmx.de>
Co-authored-by: zeertzjq <zeertzjq@outlook.com>

src/nvim/api/extmark.c

@@ -389,7 +389,7 @@ Array nvim_buf_get_extmarks(Buffer buffer, Integer ns_id, Object start, Object e
 ///               - virt_text : virtual text to link to this mark.
 ///                   A list of [text, highlight] tuples, each representing a
 ///                   text chunk with specified highlight. `highlight` element
-///                   can either be a a single highlight group, or an array of
+///                   can either be a single highlight group, or an array of
 ///                   multiple highlight groups that will be stacked
 ///                   (highest priority last). A highlight group can be supplied
 ///                   either as a string or as an integer, the latter which

src/nvim/api/window.c

@@ -430,7 +430,7 @@ Object nvim_win_call(Window window, LuaRef fun, Error *err)
 /// Set highlight namespace for a window. This will use highlights defined in
 /// this namespace, but fall back to global highlights (ns=0) when missing.
 ///
-/// This takes predecence over the 'winhighlight' option.
+/// This takes precedence over the 'winhighlight' option.
 ///
 /// @param ns_id the namespace to use
 /// @param[out] err Error details, if any