Declare missing direct dependencies

The package imports `frequenz.client.common`, `frequenz.core` and
`grpc` directly, but none of them was declared in pyproject.toml; they
were only pulled in transitively through `frequenz-client-dispatch`.
If that client changed its own requirements (for example to accept
`frequenz-client-common` v0.4.x), this library could break without any
warning from the resolver.

Declare all three explicitly. `frequenz-client-common` is pinned to `>=
0.3.8, < 0.4.0` as the issue suggests and `frequenz-core` follows what
the minimum supported `frequenz-client-dispatch` (0.11.3) requires. The
`grpcio` floor is 1.80.0 because `frequenz-client-common` 0.3.8 needs
`frequenz-api-common >= 0.8.4`, which itself requires `grpcio >= 1.80`.

Signed-off-by: Leandro Lucarella <luca-frequenz@llucax.com>

Author: llucax

RELEASE_NOTES.md

@@ -23,3 +23,6 @@
 * Fixed documentation cross-references to dependencies by updating the
   mkdocstrings inventories to match the minimum dependency versions and
   adding the missing `frequenz-client-base` inventory.
+* Declared the missing direct dependencies `frequenz-client-common`,
+  `frequenz-core` and `grpcio`, which were previously only pulled in
+  indirectly through `frequenz-client-dispatch`.

pyproject.toml

@@ -42,6 +42,9 @@ dependencies = [
   "frequenz-channels >= 1.6.1, < 2.0.0",
   "frequenz-client-dispatch >= 0.11.3, < 2.0.0",
   "frequenz-client-base >= 0.11.0, < 0.12.0",
+  "frequenz-client-common >= 0.3.8, < 0.4.0",
+  "frequenz-core >= 1.0.2, < 2.0.0",
+  "grpcio >= 1.80.0, < 2.0.0",
 ]
 dynamic = ["version"]