Fix Style/SymbolProc offenses

This also provides a performance improvement

```
Comparison (array of 4 elements):
              map(&):  3643131.4 i/s
              map {}:  3488052.5 i/s - 1.04x  (± 0.00) slower

Comparison (array of 20 elements):
              map(&):   466013.9 i/s
              map {}:   408447.2 i/s - 1.14x  (± 0.00) slower
```

1 files changed, 2 insertions, 2 deletions

diff --git a/lib/axlsx/drawing/drawing.rb b/lib/axlsx/drawing/drawing.rb
index 8cb3e2cc..fa7a608c 100644
--- a/lib/axlsx/drawing/drawing.rb
+++ b/lib/axlsx/drawing/drawing.rb
@@ -109,14 +109,14 @@ module Axlsx
     # @return [Array]
     def hyperlinks
       links = self.images.select { |a| a.hyperlink.is_a?(Hyperlink) }
-      links.map { |a| a.hyperlink }
+      links.map(&:hyperlink)
     end
 
     # An array of image objects that are associated with this drawing's anchors
     # @return [Array]
     def images
       images = @anchors.select { |a| a.object.is_a?(Pic) }
-      images.map { |a| a.object }
+      images.map(&:object)
     end
 
     # The index of this drawing in the owning workbooks's drawings collection.