Fix ignored lib directory (#40)

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## Description
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`miniz` directory was incorrectly named `miniz.c`

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It was not correctly ignored.

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.devcontainer/devcontainer.json

@@ -19,7 +19,7 @@
                     "src/libs/libspng",
                     "src/libs/mini.c",
                     "src/libs/minimp3",
-                    "src/libs/miniz.c"
+                    "src/libs/miniz"
                 ]
             }
         }