Fix go version check for busybox sh

`printf` in busybox emits a ugly 'invalid number' error when formatting
string variables are present. Avoid that by reducing the go version
check to just two digits, which ought to be enough as patch-level go
versions are meant to be compatible.

Makefile

@@ -201,9 +201,9 @@ help:
 
 .PHONY: go-check
 go-check:
-	$(eval MIN_GO_VERSION_STR := $(shell grep -Eo '^go\s+[0-9]+\.[0-9.]+' go.mod | cut -d' ' -f2))
-	$(eval MIN_GO_VERSION := $(shell printf "%03d%03d%03d" $(shell echo '$(MIN_GO_VERSION_STR)' | tr '.' ' ')))
-	$(eval GO_VERSION := $(shell printf "%03d%03d%03d" $(shell $(GO) version | grep -Eo '[0-9]+\.[0-9.]+' | tr '.' ' ');))
+	$(eval MIN_GO_VERSION_STR := $(shell grep -Eo '^go\s+[0-9]+\.[0-9]+' go.mod | cut -d' ' -f2))
+	$(eval MIN_GO_VERSION := $(shell printf "%03d%03d" $(shell echo '$(MIN_GO_VERSION_STR)' | tr '.' ' ')))
+	$(eval GO_VERSION := $(shell printf "%03d%03d" $(shell $(GO) version | grep -Eo '[0-9]+\.[0-9]+' | tr '.' ' ');))
 	@if [ "$(GO_VERSION)" -lt "$(MIN_GO_VERSION)" ]; then \
 		echo "Gitea requires Go $(MIN_GO_VERSION_STR) or greater to build. You can get it at https://go.dev/dl/"; \
 		exit 1; \