Fix treasury spend origin

[RomarQ]

What does it do?

Following the upgrade to the Polkadot SDK stable2407 (see Update moonbeam to polkadot stable2407 by gonzamontiel · Pull Request #2932 · moonbeam-foundation/moonbeam), a regression was introduced in the runtime that breaks the existing Treasury spending proposal flow (as described here).

Following the upgrade to RT3300, it is not possible anymore to create a Treasury spending proposal:

The proposed correction is to create a RootOrTreasuryCouncilOrigin origin (to be configured as SpendOrigin on the Treasury pallet).

[github-actions]

WASM runtime size check:

Compared to target branch

Moonbase runtime: 2272 KB (no changes) ✅

Moonbeam runtime: 2248 KB (no changes) ✅

Moonriver runtime: 2240 KB (no changes) ✅

Compared to latest release (runtime-3400)

Moonbase runtime: 2272 KB (+244 KB compared to latest release) ⚠️

Moonbeam runtime: 2248 KB (+236 KB compared to latest release) ⚠️

Moonriver runtime: 2240 KB (+228 KB compared to latest release) ⚠️

[github-actions]

Coverage Report

@@                       Coverage Diff                        @@
##           master   rq/fix-treasury-spend-origin      +/-   ##
================================================================
+ Coverage   74.47%                         74.59%   +0.12%     
  Files         377                            377              
+ Lines       95720                          96033     +313     
================================================================
+ Hits        71283                          71632     +349     
- Misses      24437                          24401      -36     

Files Changed	Coverage
/primitives/account/src/lib.rs	64.84% (+2.34%)	🔼
/runtime/moonbase/src/lib.rs	50.60% (+0.26%)	🔼
/runtime/moonbase/src/weights/pallet_treasury.rs	13.24% (+13.24%)	🔼
/runtime/moonbase/tests/integration_test.rs	99.42% (+0.03%)	🔼
/runtime/moonbeam/src/lib.rs	44.65% (+0.24%)	🔼
/runtime/moonbeam/src/weights/pallet_treasury.rs	13.24% (+13.24%)	🔼
/runtime/moonbeam/tests/integration_test.rs	99.41% (+0.02%)	🔼
/runtime/moonriver/src/lib.rs	44.87% (+0.24%)	🔼
/runtime/moonriver/src/weights/pallet_treasury.rs	13.24% (+13.24%)	🔼
/runtime/moonriver/tests/integration_test.rs	99.39% (+0.02%)	🔼

Coverage generated Wed Jan 15 16:51:06 UTC 2025

[pLabarta]

New tests look good. Failing CI is due to guidelines, the branding guidelines site, being down and probably in process of being updated; should be safe to ignore.