Refactor: Change Pool API to have separate methods for `JoinPool` and `JoinPoolNoSwap`

[AlpinYukseloglu]

Closes: #2128

What is the purpose of the change

Add JoinPoolNoSwap and CalcJoinPoolNoSwapShares to our GAMM pool interface to have a clear and accessible flow for no-swap joins.

Brief Changelog

• Add JoinPoolNoSwap and CalcJoinPoolNoSwapShares to GAMM pool interface
• Implement JoinPoolNoSwap and CalcJoinPoolNoSwapShares in balancer package
• Route JoinPoolNoSwap in pool_service.go to the new JoinPoolNoSwap in our pool interface
• Add tests for new balancer methods

TODO:

• Create issue for stableswap implementation

Testing and Verifying

This change added tests and can be verified as follows:

• TestCalcJoinPoolNoSwapShares in balancer's pool_test.go

Documentation and Release Note

• Does this pull request introduce a new feature or user-facing behavior changes? (no)
• Is a relevant changelog entry added to the Unreleased section in CHANGELOG.md? (yes)
• How is the feature or change documented? (not documented)

[github-actions[bot]]

This pull request has been automatically marked as stale because it has not had any recent activity. It will be closed if no further activity occurs. Thank you!