Fix loop in YYTextDrawInnerShadow()

Ref: ibireme#876

Author: yanyin1986

YYText/Component/YYTextLayout.m

@@ -3098,7 +3098,10 @@ static void YYTextDrawInnerShadow(YYTextLayout *layout, CGContextRef context, CG
                 CTRunGetPositions(run, CFRangeMake(0, 1), &runPosition);
                 CGRect runImageBounds = CTRunGetImageBounds(run, context, CFRangeMake(0, 0));
                 runImageBounds.origin.x += runPosition.x;
-                if (runImageBounds.size.width < 0.1 || runImageBounds.size.height < 0.1) continue;
+                if (runImageBounds.size.width < 0.1 || runImageBounds.size.height < 0.1) {
+                    shadow = shadow.subShadow;
+                    continue;
+                }
 
                 CFDictionaryRef runAttrs = CTRunGetAttributes(run);
                 NSValue *glyphTransformValue = CFDictionaryGetValue(runAttrs, (__bridge const void *)(YYTextGlyphTransformAttributeName));