Allow stellar ledger device to sign `stellar contract invoke` directly

[elizabethengelman]

Allow for signing contract invoke with ledger. This currently returns an error: ❌ error: Ledger cannot reveal private keys

There is a work around, where you can invoke the tx with --build-only and then pipe the tx to stellar tx sign --sign-with-ledger.

[github-actions]

This issue is stale because it has been assigned for 30 days with no activity. It will be closed in 90 days unless the stale label is removed, and the assignee is removed or updated.

[github-actions]

This issue is stale because it has been assigned for 30 days with no activity. It will be closed in 90 days unless the stale label is removed, and the assignee is removed or updated.

[github-actions]

This issue is stale because it has been assigned for 30 days with no activity. It will be closed in 90 days unless the stale label is removed, and the assignee is removed or updated.