Declare jinja2 as a direct dependency

fastapi_cache.coder imports starlette.templating unconditionally, which
requires jinja2. Since Starlette 1.0 no longer bundles jinja2 (it's an
optional extra), a minimal install crashes with 'ImportError: jinja2 must
be installed to use Jinja2Templates'. The test suite missed this because
the dev group pulls in jinja2 transitively via towncrier.

Fixes #568

Author: jkukul

changelog.d/568.bugfix.md

@@ -0,0 +1 @@
+Declare `jinja2` as a direct dependency. `fastapi_cache.coder` imports `starlette.templating` unconditionally, which requires jinja2, but jinja2 is only an optional starlette extra (dropped from the base install in Starlette 1.0). This fixes `ImportError: jinja2 must be installed to use Jinja2Templates` on a minimal install.

poetry.lock

@@ -21,6 +21,10 @@ uvicorn = "*"
 typing-extensions = { version = ">=4.1.0" }
 importlib-metadata = { version = "^6.6.0", python = "<3.8" }
 pendulum = "^3.0.0"
+# coder.py imports starlette.templating unconditionally, which requires jinja2.
+# jinja2 is only an optional starlette extra (dropped from the base install in
+# Starlette 1.0), so declare it explicitly here.
+jinja2 = "*"
 aiomcache = { version = "^0.8.2", optional = true }
 aiobotocore = {version = "^2.13.1", optional = true}
 redis = {version = "^5.0.8", extras = ["redis"]}