frank-small quadlet: Entry -> Entrypoint (actual v1 generator key)

podman 5.7.0's v1 quadlet generator rejects both ContainerEntrypoint
and Entry; the key is Entrypoint= (pkg/systemd/quadlet/quadlet.go
KeyEntrypoint, mapped to --entrypoint).

tests/frank_small_unit.bats

@@ -62,7 +62,7 @@ QUADLET_LARGE="$REPO_ROOT/dankclaw/frank-large/quadlet/frank-large.container"
 }
 
 @test "frank-small runs the repo's own entrypoint with the repo's env" {
-    grep -q '^Entry=/scripts/serve-frank-small.sh$' "$QUADLET"
+    grep -q '^Entrypoint=/scripts/serve-frank-small.sh$' "$QUADLET"
     grep -q '^Environment=FRANK_SMALL_ENV_FILE=/scripts/frank-small.env$' "$QUADLET"
     grep -q 'Volume=/home/dank/serverAppConfigs/scripts:/scripts:ro' "$QUADLET"
 }