net/synapse: fix build with setuptools_rust 1.6.0

relax the version check, probably forgotten
in matrix-org/synapse#15512

build failure reported by ajacoutot@

net/synapse/patches/patch-pyproject_toml

@@ -3,7 +3,7 @@ No need to run-depend on setuptools_rust and rust..
 Index: pyproject.toml
 --- pyproject.toml.orig
 +++ pyproject.toml
-@@ -182,7 +182,7 @@ pydantic = ">=1.7.4"
+@@ -217,7 +217,7 @@ pydantic = ">=1.7.4"
  # This isn't really a dev-dependency, as `poetry install --no-dev` will fail,
  # but the alternative is to add it to the main list of deps where it isn't
  # needed.
@@ -12,3 +12,12 @@ Index: pyproject.toml
 
 
  # Optional Dependencies
+@@ -368,7 +368,7 @@ furo = ">=2022.12.7,<2024.0.0"
+ # system changes.
+ # We are happy to raise these upper bounds upon request,
+ # provided we check that it's safe to do so (i.e. that CI passes).
+-requires = ["poetry-core>=1.0.0,<=1.5.0", "setuptools_rust>=1.3,<=1.5.2"]
++requires = ["poetry-core>=1.0.0,<=1.5.0", "setuptools_rust>=1.3,<=1.6.0"]
+ build-backend = "poetry.core.masonry.api"
+
+