patch 9.1.1319: Various typos in the code, issue with test_inst_complete.vim

Problem:  Various typos in the code, redundant and strange use of
          :execute in test_ins_complete.vim (after 9.1.1315).
Solution: Fix typos in the code and in the documentation, use the
          executed command directly (zeertzjq).

closes: #17143

Co-authored-by: Christ van Willegen <cvwillegen@gmail.com>
Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/doc/develop.txt b/runtime/doc/develop.txt
index d97d230..18e2cae 100644
--- a/runtime/doc/develop.txt
+++ b/runtime/doc/develop.txt
@@ -1,4 +1,4 @@
-*develop.txt*   For Vim version 9.1.  Last change: 2024 Dec 25
+*develop.txt*   For Vim version 9.1.  Last change: 2025 Apr 18
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -192,7 +192,7 @@
 since this triggers the test suite.
 
 							*style-clang-format*
-sound.c and sign.c can be (semi-) automatically formated using the
+sound.c and sign.c can be (semi-) automatically formatted using the
 `clang-format` formatter according to the distributed .clang-format file.
 Other source files do not yet correspond to the .clang-format file.  This may
 change in the future and they may be reformatted as well.