Fix v4 versioning to match v3 for build number

Our versioning for v4 follows SemVer, but appends the patch version as the build number.

**Ex:**
`v4.1.3` becomes `v4.1.3.3` in the Azure Portal.
`v3.3.1` appears as `v3.3.1.0` by comparison. This is the correct versioning.

We need to update how versioning is handled when we build to ensure consistency across `v4` and `v3`.

[Example PR.](https://github.com/Azure/azure-functions-docker/pull/587/files) I am not sure if this could be attributed to the host repo or not; we can move it if need be.

Start by comparing how v3 and v4 version numbers are handled during builds, using the linked example PR as the main reference. Confirm the change belongs in this repository rather than the host repo, and consider the work complete when v4 build output matches v3 without appending the patch version as the Azure Portal build number.

Written by the indexing model from the issue text.