Update outline/square-minus and outline/square-minus-2 to match outline/square-plus and outline/square-plus-2 (#1390)

* Rename square-minus to square-minus-2

The svg matches outline/square-plus-2 and does not match
filled/square-minus. This is the correct name for the svg

* Update tags for outline/square-minus-2.svg to match outline/square-plus-2.svg

* Add missing outline/square-minus.svg icon based on the outline/square-plus.svg icon

icons/outline/square-minus-2.svg

@@ -0,0 +1,20 @@
+<!--
+category: Shapes
+tags: [geometry, subtraction, math, symbol, calculate, decrease, subtract, count, diminish, reduce, indeterminate, remove]
+version: "1.0"
+unicode: "eb29"
+-->
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <path d="M12.5 21h-7.5a2 2 0 0 1 -2 -2v-14a2 2 0 0 1 2 -2h14a2 2 0 0 1 2 2v10" />
+  <path d="M16 19h6" />
+</svg>

icons/outline/square-minus.svg

@@ -1,8 +1,8 @@
 <!--
 category: Shapes
-tags: [remove, indeterminate]
+tags: [remove, delete]
 version: "1.0"
-unicode: "eb29"
+unicode: "1018b"
 -->
 <svg
   xmlns="http://www.w3.org/2000/svg"
@@ -15,6 +15,6 @@ unicode: "eb29"
   stroke-linecap="round"
   stroke-linejoin="round"
 >
-  <path d="M12.5 21h-7.5a2 2 0 0 1 -2 -2v-14a2 2 0 0 1 2 -2h14a2 2 0 0 1 2 2v10" />
-  <path d="M16 19h6" />
+  <path d="M9 12h6" />
+  <path d="M3 5a2 2 0 0 1 2 -2h14a2 2 0 0 1 2 2v14a2 2 0 0 1 -2 2h-14a2 2 0 0 1 -2 -2v-14z" />
 </svg>