fix: open hamburger dropdown to the right so it doesn't cover the CCB

The hamburger menu's dropdown was anchored with `right: 0; left: auto`,
which aligned its right edge with the toggle's right edge and made it
extend leftward. In the narrow-titlebar layout that shows the hamburger
the dropdown would spill over the central control bar, overlapping the
editor / design-mode buttons.

Flip to `left: 0; right: auto` so the dropdown's left edge aligns with
the toggle and opens into the empty titlebar area on the right.
Submenu arrows already point right (►), so submenu cascade direction is
unchanged.

Author: abose

src/styles/brackets_patterns_override.less

@@ -239,8 +239,8 @@ a:focus {
             display: none;
             min-width: 120px;
             text-align: left;
-            right: 0;
-            left: auto;
+            left: 0;
+            right: auto;
         }
         &.hamburger-open .hamburger-dropdown {
             display: block;