Extract component to render an execution

Note that, in order to be consistent with the name of the component,
we're renaming the `budget-execution` class to
`budget-executions-investment`.

app/assets/stylesheets/budgets/executions/investment.scss

@@ -0,0 +1,54 @@
+.budget-executions-investment {
+  @include card;
+  border: 1px solid $border;
+  overflow: hidden;
+  position: relative;
+
+  a {
+    color: inherit;
+    display: block;
+
+    img {
+      height: $line-height * 9;
+      max-width: none;
+      min-width: 100%;
+      transition-duration: 0.3s;
+      transition-property: transform;
+    }
+
+    &:hover {
+      text-decoration: none;
+
+      img {
+        transform: scale(1.05);
+      }
+    }
+  }
+
+  h5 {
+    font-size: $base-font-size;
+    margin-bottom: 0;
+  }
+
+  .budget-execution-info {
+    padding: calc(#{$line-height} / 2);
+  }
+
+  .author {
+    color: $text-medium;
+    font-size: $small-font-size;
+  }
+
+  .budget-execution-content {
+    min-height: $line-height * 3;
+  }
+
+  .price {
+    color: $budget;
+    font-size: rem-calc(24);
+  }
+
+  &:hover:not(:focus-within) {
+    box-shadow: 0 0 12px 0 rgba(0, 0, 0, 0.2);
+  }
+}