Improve case consistency for initialisms
As it is suggested in #468 (closed) to handle the issue in multiple MRs, this MR does not include all of the needed renamings, but only the following:
- Rename connectionsByProjectId to connectionsByProjectID
- Rename GetConnectionsByProjectId to GetConnectionsByProjectID
- Rename connectionsByAgentId to connectionsByAgentID
- Rename QuerierGetConnectionsByAgentIdCall to QuerierGetConnectionsByAgentIDCall
- Rename GetConnectionsByAgentId to GetConnectionsByAgentID
See https://go.dev/wiki/CodeReviewComments#initialisms for more information.