Update libpng from 1.6.47 to 1.6.48 (#2296)

* Update libpng from 1.6.47 to 1.6.48

* Update tests

---------

Co-authored-by: emscripten-forge-bot <[email protected]>
Co-authored-by: Isabel Paredes <[email protected]>

Author: emscripten-forge-bot

recipes/recipes_emscripten/libpng/recipe.yaml

@@ -1,18 +1,17 @@
 context:
   name: libpng
-  version: 1.6.47
+  version: 1.6.48
 
 package:
   name: ${{ name }}
   version: ${{ version }}
 
 source:
-  url: http://downloads.sourceforge.net/project/${{ name }}/libpng16/${{ version }}/${{
-    name }}-${{ version }}.tar.gz
-  sha256: 084115c62fe023e3d88cd78764a4d8e89763985ee4b4a085825f7a00d85eafbb
+  url: http://downloads.sourceforge.net/project/${{ name }}/libpng16/${{ version }}/${{ name }}-${{ version }}.tar.gz
+  sha256: 68f3d83a79d81dfcb0a439d62b411aa257bb4973d7c67cd1ff8bdf8d011538cd
 
 build:
-  number: 1
+  number: 0
 
 requirements:
   build:
@@ -23,13 +22,11 @@ requirements:
 
 tests:
 - package_contents:
-    bin:
-    - pngfix.wasm
-    - png-fix-itxt.wasm
-    lib:
-    - libpng16.a
-    include:
-    - png.h
+    files:
+    - bin/pngfix.wasm
+    - bin/png-fix-itxt.wasm
+    - lib/libpng16.a
+    - include/png.h
 - script:
   - libpng-config --version