tools/docker: Add VERBOSE option

tools/docker/Makefile

@@ -132,6 +132,7 @@ help:
 	@echo -e "\te.g. 'make arm64_almalinux-9_export'"
 	@echo
 	@echo -e "\t${BOLD}NOCACHE=1${RESET}: use 'docker build --no-cache' when building container (default use cache)."
+	@echo -e "\t${BOLD}VERBOSE=1${RESET}: use 'docker build --progress=plain' when building container."
 	@echo
 	@echo -e "${BOLD}NOTES${RESET}"
 	@echo -e "\tAll generated code will be located in the export/ folder, use target ${BOLD}distclean${RESET} to remove it."
@@ -161,14 +162,16 @@ $(info version: ${OR_TOOLS_VERSION})
 # Docker image name prefix.
 IMAGE := or-tools/docker
 
-ifdef NOCACHE
-DOCKER_BUILD_CMD := docker build --no-cache
-DOCKER_BUILDX_CMD := docker buildx build --no-cache
-else
 DOCKER_BUILD_CMD := docker build
 DOCKER_BUILDX_CMD := docker buildx build
+ifdef NOCACHE
+DOCKER_BUILD_CMD := ${DOCKER_BUILD_CMD} --no-cache
+DOCKER_BUILDX_CMD := ${DOCKER_BUILDX_CMD} --no-cache
+endif
+ifdef VERBOSE
+DOCKER_BUILD_CMD := ${DOCKER_BUILD_CMD} --progress=plain
+DOCKER_BUILDX_CMD := ${DOCKER_BUILDX_CMD} --progress=plain
 endif
-DOCKER_RUN_CMD := docker run --rm --init
 
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 ###  DELIVERY  ##