vim-patch:8.0.0876: backslashes and wildcards in backticks don't work

Problem:    MS-Windows: Backslashes and wildcards in backticks don't work.
Solution:   Do not handle backslashes inside backticks in the wrong place.
            (Yasuhiro Matsumoto, closes vim/vim#1942)
39d21e3c30

src/nvim/path.c

@@ -1346,6 +1346,15 @@ void slash_adjust(char_u *p)
   if (path_with_url((const char *)p)) {
     return;
   }
+
+  if (*p == '`') {
+    // don't replace backslash in backtick quoted strings
+    const size_t len = STRLEN(p);
+    if (len > 2 && *(p + len - 1) == '`') {
+      return;
+    }
+  }
+
   while (*p) {
     if (*p == (char_u)psepcN) {
       *p = (char_u)psepc;