chore: update pipenv install strategy (tested on ubuntu-22.04)

docs/Pipfile

@@ -10,4 +10,4 @@ sphinx = "*"
 sphinx-rtd-theme = "*"
 
 [requires]
-python_version = "3.9"
+python_version = "3.10"

docs/Pipfile.lock

@@ -1,11 +1,11 @@
 {
     "_meta": {
         "hash": {
-            "sha256": "dbc8cbda5085f2fce5e6fdb2f9e922673537e7bfaad8b9f9a4c349ca0d4c3d9c"
+            "sha256": "cda229a62af7070dfa5000f2e03fbfd29bc4df7fbc0f219e026d849f433d339f"
         },
         "pipfile-spec": 6,
         "requires": {
-            "python_version": "3.9"
+            "python_version": "3.10"
         },
         "sources": [
             {
@@ -157,14 +157,6 @@
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
             "version": "==1.4.1"
         },
-        "importlib-metadata": {
-            "hashes": [
-                "sha256:7efb448ec9a5e313a57655d35aa54cd3e01b7e1fbcf72dce1bf06119420f5bad",
-                "sha256:e354bedeb60efa6affdcc8ae121b73544a7aa74156d047311948f6d711cd378d"
-            ],
-            "markers": "python_version < '3.10'",
-            "version": "==6.0.0"
-        },
         "jinja2": {
             "hashes": [
                 "sha256:31351a702a408a9e7595a8fc6150fc3f43bb6bf7e319770cbc0db9df9437e852",
@@ -338,14 +330,6 @@
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4, 3.5'",
             "version": "==1.26.14"
-        },
-        "zipp": {
-            "hashes": [
-                "sha256:83a28fcb75844b5c0cdaf5aa4003c2d728c77e05f5aeabe8e95e56727005fbaa",
-                "sha256:a7a22e05929290a67401440b39690ae6563279bced5f314609d9d03798f56766"
-            ],
-            "markers": "python_version >= '3.7'",
-            "version": "==3.11.0"
         }
     },
     "develop": {}