Remove requirement for presence of type with redirect= option

Related issue:
- https://github.com/gorhill/uBlock/issues/3590

Since the `redirect=` option was refactored into a modifier
filter, presence of a type (`script`, `xhr`, etc.) is no
longer a requirement.

docs/tests/static-filtering-parser-checklist.txt

@@ -42,6 +42,7 @@ a*
 
 ! valid options
 $script,redirect=noop.js
+*$redirect=noop.js
 *$empty
 *$xhr,empty
 *$xhr,redirect=empty
@@ -91,9 +92,6 @@ $
 ! bad regex
 /(abc|def/$xhr
 
-! can't redirect without type (except to `empty`)
-*$redirect=noop.js
-
 ! non-redirectable types
 *$beacon,redirect-rule=empty
 *$ping,redirect-rule=empty

src/js/static-filtering-parser.js

@@ -2383,18 +2383,13 @@ const NetOptionsIterator = class {
                 }
             }
         }
-        // `redirect=`: requires at least one single redirectable type
+        // `redirect=`: can't redirect non-redirectable types
         {
             let i = this.tokenPos[OPTTokenRedirect];
             if ( i === -1 ) {
                 i = this.tokenPos[OPTTokenRedirectRule];
             }
-            if (
-                i !== -1 && (
-                    hasNoBits(allBits, OPTRedirectableType) ||
-                    hasBits(allBits, OPTNonRedirectableType)
-                )
-            ) {
+            if ( i !== -1 && hasBits(allBits, OPTNonRedirectableType) ) {
                 optSlices[i] = OPTTokenInvalid;
                 if ( this.interactive ) {
                     this.parser.errorSlices(optSlices[i+1], optSlices[i+5]);