Fix Mockery Warning

[winder]

Subject of the issue

Address mockery warning, we need to install the binary directly instead of using go intall:

~$ make test
go install github.com/vektra/mockery/v2@v2.12.3
cd idb && mockery --name=IndexerDb
13 Jul 22 08:13 EDT INF Starting mockery dry-run=false version=v2.12.3
13 Jul 22 08:13 EDT WRN !!! DEPRECATION NOTICE !!! dry-run=false version=v2.12.3
13 Jul 22 08:13 EDT WRN Using go install to download mockery will likely break after June 1, 2022. Please view PR #456 for details. dry-run=false version=v2.12.3
13 Jul 22 08:13 EDT INF Walking dry-run=false version=v2.12.3
13 Jul 22 08:13 EDT INF Generating mock dry-run=false interface=IndexerDb qualified-name=github.com/algorand/indexer/idb version=v2.12.3

[winder]

It looks like we can update to a slightly newer version, and the warning is removed:

vektra/mockery#456 (comment)