patch 8.1.0139: Lua tests fail on some platforms

Problem:    Lua tests fail on some platforms.
Solution:   Accept a hex number with and without "0x". (Ken Takata,
            closes #3137)

src/testdir/test_lua.vim

@@ -305,7 +305,7 @@ func Test_list()
  lua l:add(vim.eval("{'a':1, 'b':2, 'c':3}"))
  call assert_equal([123.0, 'abc', v:true, v:false, [1, 2, 3], {'a': 1, 'b': 2, 'c': 3}], l)
  call assert_equal(6.0, luaeval('#l'))
  call assert_match('^list: 0x\x\+$', luaeval('tostring(l)'))
  call assert_match('^list: \%(0x\)\?\x\+$', luaeval('tostring(l)'))

  lua l[0] = 124
  lua l[4] = nil
@@ -358,7 +358,7 @@ func Test_recursive_list()

  call assert_equal('[1.0, 2.0, [...]]', string(luaeval('l')))

  call assert_match('^list: 0x\x\+$', luaeval('tostring(l)'))
  call assert_match('^list: \%(0x\)\?\x\+$', luaeval('tostring(l)'))
  call assert_equal(luaeval('tostring(l)'), luaeval('tostring(l[2])'))

  call assert_equal(luaeval('l'), luaeval('l[2]'))
@@ -380,7 +380,7 @@ func Test_dict()
  lua d[5] = vim.eval("{'a':1, 'b':2, 'c':3}")
  call assert_equal({'0':123.0, '1':'abc', '2':v:true, '3':v:false, '4': [1, 2, 3], '5': {'a':1, 'b':2, 'c':3}}, d)
  call assert_equal(6.0, luaeval('#d'))
  call assert_match('^dict: 0x\x\+$', luaeval('tostring(d)'))
  call assert_match('^dict: \%(0x\)\?\x\+$', luaeval('tostring(d)'))

  call assert_equal('abc', luaeval('d[1]'))

src/version.c

@@ -789,6 +789,8 @@ static char *(features[]) =

static int included_patches[] =
{   /* Add new patch number below this line */
/**/
    139,
/**/
    138,
/**/