Pin the pyright version until I understand what's changed.

In 308 (and 309) somehow I get impossible looking errors, particularly one
looking like:

/Users/julian/Development/referencing/referencing/_core.py:344:52 -
    error: Argument of type "Resource[D@Registry]" cannot be assigned to
    parameter "resource" of type "Resource[D@Registry]" in function
    "with_resource"
    "referencing._core.Resource" is incompatible with "referencing._core.Resource"

but lots of others saying things like

  /Users/julian/Development/referencing/referencing/_core.py:125:29 -
    error: Argument of type "Specification[D@Resource]" cannot be assigned
    to parameter "default" of type "Specification[Any]" in function
    "specification_with" "Specification[D@Resource]" is incompatible with
    "Specification[Any]" (reportGeneralTypeIssues)

where I don't understand why Any is not sufficent for the bound type
variables, but then again I had trouble understanding why I couldn't use the
same bound variables in some of those places anyhow.

noxfile.py

@@ -54,7 +54,7 @@ def style(session):
 
 @session()
 def typing(session):
-    session.install("pyright", ROOT)
+    session.install("pyright==1.1.307", ROOT)
     session.run("pyright", REFERENCING)