Fix not highlighting cases of invalid syntax

Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/1791

The following case of invalid syntax was not reported as
invalid by the syntax highlighter:

    ... example.com image ...

With dynamic filtering, there can't be a specific
hostname when a specific type is used, or a
specific type when a specific hostname is used, one
or the other must be `*`.

src/js/codemirror/ubo-dynamic-filtering.js

@@ -123,6 +123,7 @@ CodeMirror.defineMode('ubo-dynamic-filtering', ( ) => {
         const { sortType } = opts;
         const reNotToken = /^\s+/;
         const reToken = /^\S+/;
+        const tokens = [];
         // leading whitespaces
         let match = reNotToken.exec(string);
         if ( match !== null ) {
@@ -131,6 +132,7 @@ CodeMirror.defineMode('ubo-dynamic-filtering', ( ) => {
         // first token
         match = reToken.exec(string);
         if ( match === null ) { return; }
+        tokens.push(match[0]);
         // hostname or switch
         const isSwitchRule = validSwitches.has(match[0]);
         if ( isSwitchRule ) {
@@ -151,6 +153,7 @@ CodeMirror.defineMode('ubo-dynamic-filtering', ( ) => {
         // second token
         match = reToken.exec(string);
         if ( match === null ) { return; }
+        tokens.push(match[0]);
         // hostname or url
         const isURLRule = isSwitchRule === false && match[0].indexOf('://') > 0;
         if ( isURLRule ) {
@@ -169,6 +172,7 @@ CodeMirror.defineMode('ubo-dynamic-filtering', ( ) => {
         // third token
         match = reToken.exec(string);
         if ( match === null ) { return; }
+        tokens.push(match[0]);
         // rule type or switch state
         if ( isSwitchRule ) {
             string = validSwitcheStates.has(match[0])
@@ -178,10 +182,14 @@ CodeMirror.defineMode('ubo-dynamic-filtering', ( ) => {
             string = invalidURLRuleTypes.has(match[0])
                 ? addMatchSlice(match, 'error')
                 : addMatchSlice(match);
-        } else {
+        } else if ( tokens[1] === '*' ) {
             string = validHnRuleTypes.has(match[0])
                 ? addMatchSlice(match)
                 : addMatchSlice(match, 'error');
+        } else {
+            string = match[0] === '*'
+                ? addMatchSlice(match)
+                : addMatchSlice(match, 'error');
         }
         // whitespaces before fourth token
         match = reNotToken.exec(string);
@@ -190,6 +198,7 @@ CodeMirror.defineMode('ubo-dynamic-filtering', ( ) => {
         // fourth token
         match = reToken.exec(string);
         if ( match === null ) { return; }
+        tokens.push(match[0]);
         string = isSwitchRule || validActions.has(match[0]) === false
             ? addMatchSlice(match, 'error')
             : addMatchSlice(match, `${match[0]}rule`);