Copy over the viewBox, width, and height attributes of the light social icons to dark icons

static/icons/feed-dark.svg

@@ -3,8 +3,9 @@
 
 <svg
    version="1.1"
-   width="53"
-   height="53"
+   viewBox="1 5 48 48"
+   width="48"
+   height="48"
    id="svg61"
    sodipodi:docname="rss-dark.svg"
    inkscape:version="1.1.1 (c3084ef, 2021-09-22)"

static/icons/github-dark.svg

@@ -1,11 +1,9 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
 <svg
-   viewBox="1 2 49 48"
    version="1.1"
    id="svg308"
    sodipodi:docname="github-dark.svg"
-   width="47"
-   height="47"
+   viewBox="1 2 49 48"
    inkscape:version="1.1.1 (c3084ef, 2021-09-22)"
    xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
    xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"

static/icons/github.svg

@@ -1,9 +1,9 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
 <svg
-   viewBox="1 2 49 48"
    version="1.1"
    id="svg308"
    sodipodi:docname="github.svg"
+   viewBox="1 2 49 48"
    width="47"
    height="47"
    inkscape:version="1.1.1 (c3084ef, 2021-09-22)"

static/icons/instagram-dark.svg

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
 <svg
-   viewBox="-1.5 -3 53 53"
+   viewBox="0 0 50 50"
    version="1.1"
    id="svg1086"
    sodipodi:docname="instagram-dark.svg"