Fix apk test package naming (#961)

* modify alpine package name:
nginx-agent-3.0.0_1234 -> nginx-agent-3.0.0.1234

* protoc-gen update

Author: sean-breen

Makefile.packaging

@@ -10,7 +10,7 @@ BINARY_PATH         := $(BUILD_DIR)/$(BINARY_NAME)
 GPG_PUBLIC_KEY      := .key
 PACKAGE_BUILD       ?= 1
 PACKAGE_VERSION     := $(shell echo ${VERSION} | tr -d 'v')-$(PACKAGE_BUILD)
-APK_PACKAGE_VERSION := $(shell echo ${VERSION} | tr -d 'v')_$(PACKAGE_BUILD)
+APK_PACKAGE_VERSION := $(shell echo ${VERSION} | tr -d 'v').$(PACKAGE_BUILD)
 TARBALL_NAME        := $(PACKAGE_PREFIX)v3.tar.gz
 
 DEB_DISTROS         ?= ubuntu-noble-24.04 ubuntu-jammy-22.04 ubuntu-focal-20.04 debian-bookworm-12 debian-bullseye-11