patch 8.1.0185: running tests writes lua.vim even though it is not used

Problem:    Running tests writes lua.vim even though it is not used.
Solution:   Stop writing lua.vim.
diff --git a/src/testdir/Make_dos.mak b/src/testdir/Make_dos.mak
index 6cd8de6..6a86d3e 100644
--- a/src/testdir/Make_dos.mak
+++ b/src/testdir/Make_dos.mak
@@ -85,7 +85,6 @@
 	-if exist tiny.vim del tiny.vim
 	-if exist mbyte.vim del mbyte.vim
 	-if exist mzscheme.vim del mzscheme.vim
-	-if exist lua.vim del lua.vim
 	-if exist Xdir1 rd /s /q Xdir1
 	-if exist Xfind rd /s /q Xfind
 	-if exist XfakeHOME rd /s /q XfakeHOME
diff --git a/src/testdir/Make_ming.mak b/src/testdir/Make_ming.mak
index d66d667..7b38be5 100644
--- a/src/testdir/Make_ming.mak
+++ b/src/testdir/Make_ming.mak
@@ -75,7 +75,6 @@
 	-@if exist tiny.vim $(DEL) tiny.vim
 	-@if exist mbyte.vim $(DEL) mbyte.vim
 	-@if exist mzscheme.vim $(DEL) mzscheme.vim
-	-@if exist lua.vim $(DEL) lua.vim
 	-@if exist Xdir1 $(DELDIR) Xdir1
 	-@if exist Xfind $(DELDIR) Xfind
 	-@if exist XfakeHOME $(DELDIR) XfakeHOME
diff --git a/src/testdir/Make_vms.mms b/src/testdir/Make_vms.mms
index e97ad27..f14f6bc 100644
--- a/src/testdir/Make_vms.mms
+++ b/src/testdir/Make_vms.mms
@@ -208,6 +208,5 @@
 	-@ if "''F$SEARCH("small.vim")'"    .NES. "" then delete/noconfirm/nolog small.vim.*
 	-@ if "''F$SEARCH("mbyte.vim")'"    .NES. "" then delete/noconfirm/nolog mbyte.vim.*
 	-@ if "''F$SEARCH("mzscheme.vim")'" .NES. "" then delete/noconfirm/nolog mzscheme.vim.*
-	-@ if "''F$SEARCH("lua.vim")'"      .NES. "" then delete/noconfirm/nolog lua.vim.*
 	-@ if "''F$SEARCH("viminfo.*")'"    .NES. "" then delete/noconfirm/nolog viminfo.*.*
 
diff --git a/src/testdir/Makefile b/src/testdir/Makefile
index 459b868..57bcb3a 100644
--- a/src/testdir/Makefile
+++ b/src/testdir/Makefile
@@ -51,7 +51,7 @@
 $(SCRIPTS) $(SCRIPTS_GUI) $(NEW_TESTS): $(SCRIPTS_FIRST)
 
 RM_ON_RUN = test.out X* viminfo
-RM_ON_START = tiny.vim small.vim mbyte.vim mzscheme.vim lua.vim test.ok benchmark.out
+RM_ON_START = tiny.vim small.vim mbyte.vim mzscheme.vim test.ok benchmark.out
 RUN_VIM = VIMRUNTIME=$(SCRIPTSOURCE); export VIMRUNTIME; $(VALGRIND) $(VIMPROG) -f $(GUI_FLAG) -u unix.vim $(NO_INITS) -s dotest.in
 
 clean:
diff --git a/src/testdir/test1.in b/src/testdir/test1.in
index 735d539..8c0219e 100644
--- a/src/testdir/test1.in
+++ b/src/testdir/test1.in
@@ -15,7 +15,6 @@
 be set like small.vim above.  mbyte.vim is sourced by tests that require the
 +multi_byte feature.
 Similar logic is applied to the +mzscheme feature, using mzscheme.vim.
-Similar logic is applied to the +lua feature, using lua.vim.
 
 STARTTEST
 :" If columns or lines are too small, create wrongtermsize.
@@ -33,7 +32,6 @@
 qa!
 :w! mbyte.vim
 :w! mzscheme.vim
-:w! lua.vim
 :"
 :" If +multi_byte feature supported, make mbyte.vim empty.
 :if has("multi_byte") | sp another | w! mbyte.vim | q | endif
@@ -41,9 +39,6 @@
 :" If +mzscheme feature supported, make mzscheme.vim empty.
 :if has("mzscheme") | sp another | w! mzscheme.vim | q | endif
 :"
-:" If +lua feature supported, make lua.vim empty.
-:if has("lua") | sp another | w! lua.vim | q | endif
-:"
 :" If +eval feature supported quit here, leaving tiny.vim and small.vim empty.
 :" Otherwise write small.vim to skip the test.
 :if 1 | q! | endif
diff --git a/src/version.c b/src/version.c
index a1535f6..f638db6 100644
--- a/src/version.c
+++ b/src/version.c
@@ -790,6 +790,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    185,
+/**/
     184,
 /**/
     183,