[Backport release-0.9] docs(lsp): remove vim.lsp.sync (#23419)

docs(lsp): remove vim.lsp.sync

The module is used internally and not intended to be used by plugins or
users.

(cherry picked from commit 02d5a678fb)

Co-authored-by: Mathias Fussenegger <f.mathias@zignar.net>

runtime/doc/lsp.txt

@@ -2130,27 +2130,6 @@ start({cmd}, {cmd_args}, {dispatchers}, {extra_spawn_params})
         • `terminate()` terminates the RPC client.
 
 
-==============================================================================
-Lua module: vim.lsp.sync                                            *lsp-sync*
-
-                                                 *vim.lsp.sync.compute_diff()*
-compute_diff({___MissingCloseParenHere___})
-    Returns the range table for the difference between prev and curr lines
-
-    Parameters: ~
-      • {prev_lines}       (table) list of lines
-      • {curr_lines}       (table) list of lines
-      • {firstline}        (integer) line to begin search for first difference
-      • {lastline}         (integer) line to begin search in old_lines for
-                           last difference
-      • {new_lastline}     (integer) line to begin search in new_lines for
-                           last difference
-      • {offset_encoding}  (string) encoding requested by language server
-
-    Return: ~
-        (table) TextDocumentContentChangeEvent see https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#textDocumentContentChangeEvent
-
-
 ==============================================================================
 Lua module: vim.lsp.protocol                                    *lsp-protocol*
 

scripts/gen_vimdoc.py

@@ -217,7 +217,6 @@ CONFIG = {
             'util.lua',
             'log.lua',
             'rpc.lua',
-            'sync.lua',
             'protocol.lua',
         ],
         'files': [