* Update go to 1.15 to reduce binary size
Go made improvements to reduce binary size, cf https://golang.org/doc/go1.15
> Go 1.15 reduces typical binary sizes by around 5% compared to Go 1.14 by eliminating certain types of GC metadata and more aggressively eliminating unused type metadata.
In my test, this equates to about 3 mb diff between Go 1.13 and Go 1.15:
-rwxr-xr-x 1 root root 36M Aug 31 14:43 piper-go-113
-rwxr-xr-x 1 root root 33M Aug 31 14:44 piper-go-115
* Go Generate
* go mod tidy
Co-authored-by: Stephan Aßmus <stephan.assmus@sap.com>
Co-authored-by: Oliver Nocon <33484802+OliverNocon@users.noreply.github.com>
