Prepare for Cosmos SDK `v0.46.x`

[aljo242]

Is your feature request related to a problem? Please describe.
A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]

Cosmos SDK v0.46.x is a heavily API-breaking update. In order to update spn the following must be done:

• remove depreceated rest API imports refactor(app): remove deprecated rest imports #908
• remove the usage of sdk.Int.ToDec()
• decouple spn from ignite (this will avoid the current circular dependency)
• upgrade ibc-go to a version that is compliant with Cosmos SDK v0.46.x
• upgrade the imported x/fundraising module for compliance with Cosmos SDK v0.46.x

The ignite CLI depends on spn so this is a critical task that must be completed before spn can be upgraded in order to enable ignite to be upgraded