Ports/libpng: Update libpng to version 1.6.39

Author: https://github.com/cammo1123
Commit: https://github.com/SerenityOS/serenity/commit/5d9c4cc9e3
Pull-request: https://github.com/SerenityOS/serenity/pull/18058
Reviewed-by: https://github.com/linusg

Ports/AvailablePorts.md

@@ -136,7 +136,7 @@ This list is also available at [ports.serenityos.net](https://ports.serenityos.n
 | [`liboggz`](liboggz/)                               | liboggz                                                         | 1.1.1                    | https://www.xiph.org/oggz/                                                     |
 | [`libopenal`](libopenal/)                           | OpenAL soft                                                     | 1.21.1                   | https://openal-soft.org/                                                       |
 | [`libphysfs`](libphysfs/)                           | PhysicsFS                                                       | 3.0.2                    | https://icculus.org/physfs/                                                    |
-| [`libpng`](libpng/)                                 | libpng                                                          | 1.6.37                   | https://libpng.org/                                                            |
+| [`libpng`](libpng/)                                 | libpng                                                          | 1.6.39                   | https://libpng.org/                                                            |
 | [`libpuffy`](libpuffy/)                             | libpuffy                                                        | 1.0                      | https://github.com/ibara/libpuffy                                              |
 | [`libsixel`](libsixel/)                             | libsixel                                                        | 1.8.6                    | https://github.com/saitoha/libsixel                                            |
 | [`libsodium`](libsodium/)                           | libsodium                                                       | 1.0.18                   | https://doc.libsodium.org/                                                     |

Ports/libpng/package.sh

@@ -1,9 +1,9 @@
 #!/usr/bin/env -S bash ../.port_include.sh
-port=libpng
-version=1.6.37
-useconfigure=true
+port='libpng'
+version='1.6.39'
+useconfigure='true'
 configopts=("--disable-static" "--enable-shared")
-use_fresh_config_sub=true
-files="https://download.sourceforge.net/libpng/libpng-${version}.tar.gz libpng-${version}.tar.gz daeb2620d829575513e35fecc83f0d3791a620b9b93d800b763542ece9390fb4"
-auth_type=sha256
+use_fresh_config_sub='true'
+files="https://download.sourceforge.net/libpng/libpng-${version}.tar.gz libpng-${version}.tar.gz af4fb7f260f839919e5958e5ab01a275d4fe436d45442a36ee62f73e5beb75ba"
+auth_type='sha256'
 depends=("zlib")