Fix exception when version is missing when installing from the Hub package

.changes/unreleased/Fixes-20240425-174024.yaml

@@ -0,0 +1,7 @@
+kind: Fixes
+body: Fix exception when `version` is missing when installing from the Hub package
+  index
+time: 2024-04-25T17:40:24.465839-06:00
+custom:
+  Author: dbeatty10
+  Issue: "10048"

core/dbt/contracts/project.py

@@ -116,7 +116,7 @@ class PackageConfig(dbtClassMixin):
                         "A git package is missing the value. It is a required property."
                     )
             if isinstance(package, dict) and package.get("package"):
-                if not package["version"]:
+                if not package.get("version"):
                     raise ValidationError(
                         f"{package['package']} is missing the version. When installing from the Hub "
                         "package index, version is a required property"