Add test for `add_expression_terms_rep_period_constraints!()`

[gnawin]

This test is needed for testing capacity constraints, as the function add_expression_terms* is needed for the functions generating capacity constraints.

Blocking #1301.

Edit: together with @abelsiqueira, we decided to leave this test for later. For constraints that use this function, it is assumed that this function works good.

[github-actions]

This issue is stale because it has been open 2 months with no activity. Remove the stale label or comment, otherwise this will be closed in 5 days.

[gnawin]

I think it's best to have an epic to track all the similar issues for testing.

For example, #1373 is also about tests.

[github-actions]

This issue is stale because it has been open 6 months with no activity. Remove the stale label or comment to revive it; otherwise this will be closed in 7 days.

[datejada]

Closing this issue since the output of this function is tested in the storage balance constraint tests: https://github.com/TulipaEnergy/TulipaEnergyModel.jl/blob/main/test/test-constraint-storage-balance.jl done in PR #1586