Prevent spurious wrapping of text in logger's expression picker

Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/351

src/css/logger-ui.css

@@ -178,6 +178,7 @@ textarea {
     cursor: pointer;
     margin: 0 0.5em 0 0;
     padding: 0.5em;
+    white-space: nowrap;
     }
 #netInspector #filterExprPicker span[data-filtex]:last-of-type {
     margin: 0;