Remove restriction on cpp-argparse version

Author: mcbarton

README.md

@@ -40,7 +40,7 @@ source activate  "xeus-cpp"
 ```
 We will now install the dependencies needed to compile xeux-cpp from source within this environment by executing the following
 ```bash
-mamba install notebook cmake cxx-compiler xeus-zmq nlohmann_json=3.11.3 jupyterlab CppInterOp cpp-argparse">=3.0,<4.0" pugixml doctest -c conda-forge
+mamba install notebook cmake cxx-compiler xeus-zmq nlohmann_json=3.11.3 jupyterlab CppInterOp cpp-argparse pugixml doctest -c conda-forge
 ```
 Now you can compile the kernel from the source by executing (replace `$CONDA_PREFIX` with a custom installation prefix if need be)
 ```bash
@@ -130,9 +130,14 @@ http://xeus-cpp.readthedocs.io
 - [argparse](https://github.com/p-ranav/argparse)
 - [CppInterOp](https://github.com/compiler-research/CppInterOp)
 
+| `xeus-cpp` | `xeus-zmq`      | `CppInterOp` | `pugixml` | `nlohmann_json` |
+|------------|-----------------|--------------|-----------|-----------------|
+|  main      |  >=3.0.0,<4.0.0 | >=1.5.0      | ~1.8.1    | >=3.11.3,<4.0   |
+
+Versions `0.6.0` and prior had a restriction on the exact version of cpp-argparse used
+
 | `xeus-cpp` | `xeus-zmq`      | `CppInterOp` | `pugixml` | `cpp-argparse`| `nlohmann_json` |
 |------------|-----------------|--------------|-----------|---------------|-----------------|
-|  main      |  >=3.0.0,<4.0.0 | >=1.5.0      | ~1.8.1    | >=3.0,<4.0    | >=3.11.3,<4.0   |
 |  0.6.0     |  >=3.0.0,<4.0.0 | >=1.5.0      | ~1.8.1    | <3.1          | >=3.11.3,<4.0   |
 |  0.5.0     |  >=3.0.0,<4.0.0 | >=1.3.0      | ~1.8.1    | <3.1          | >=3.11.3,<4.0   |
 

docs/source/InstallationAndUsage.rst

@@ -30,7 +30,7 @@ this environment by executing the following
 .. code-block:: bash
 
     mamba install notebook cmake cxx-compiler xeus-zmq nlohmann_json=3.11.3
-    jupyterlab CppInterOp cpp-argparse">=3.0,<4.0" pugixml doctest -c conda-forge
+    jupyterlab CppInterOp cpp-argparse pugixml doctest -c conda-forge
 
 Now you can compile the kernel from the source by executing (replace `$CONDA_PREFIX` 
 with a custom installation prefix if need be)

environment-dev.yml

@@ -12,7 +12,7 @@ dependencies:
   - nlohmann_json=3.11.3
   - CppInterOp
   - pugixml
-  - cpp-argparse>=3.0,<4.0
+  - cpp-argparse
   # Test dependencies
   - pytest
   - jupyter_kernel_test<0.8