fix(deps): Pin svglib to 1.5.1 due to pycairo installation failure (#1550)

The latest svglib release (1.6.0) has introduced a new dependency on pycairo, which requires system-level libraries to install correctly. This change causes the installation of easy-thumbnails[svg] to fail in environments where these libraries are not present.

This commit pins svglib to version 1.5.1 as a temporary workaround until the upstream issue is resolved.

Ref: deeplook/svglib#421

Author: payamnj

pyproject.toml

@@ -19,6 +19,13 @@ dependencies = [
     "django>=3.2",
     "django-polymorphic",
     "easy-thumbnails[svg]",
+    
+    # Pin svglib to a version below 1.6.0.
+    # The latest version (1.6.0) adds pycairo as a dependency,
+    # which requires system-level libraries and fails to install in the container.
+    # This can be removed once the issue is resolved.
+    # See: https://github.com/deeplook/svglib/issues/421
+    "svglib~=1.5.1"
 ]
 classifiers = [
     "Development Status :: 5 - Production/Stable",