Update inTextImg.html

Fix Bad value 15px for attribute height on element img: Expected a digit but saw p instead.

layouts/shortcodes/inTextImg.html

@@ -2,4 +2,4 @@
 {{- $height := (.Get "height") }}
 {{- $alt := (.Get "alt") }}
 
-<img class="in-text" height="{{ $height | default `15px` }}" src="{{$Img}}" alt="{{$alt}}">
+<img class="in-text" height="{{ $height | default `15` }}" src="{{$Img}}" alt="{{$alt}}">