build: Remove DragonOS_GCC And make CI use docker image (#954)

* build: 不再需要x86_64-elf-gcc的支持
* ci: 添加ci用的docker镜像
* 切换workflow到构建用的容器上

---------

Signed-off-by: longjin <longjin@DragonOS.org>

.vscode/settings.json

@@ -9,7 +9,6 @@
         "glib.h": "c",
         "asm.h": "c",
         "memory.h": "c",
-        "multiboot2.h": "c",
         "kprint.h": "c",
         "ptrace.h": "c",
         "mouse.h": "c",
@@ -77,7 +76,6 @@
         "cstdbool": "c",
         "typeinfo": "c",
         "unistd.h": "c",
-        "syscall_num.h": "c",
         "stdint.h": "c",
         "syscall.h": "c",
         "fcntl.h": "c",
@@ -121,9 +119,7 @@
         "dirent.h": "c",
         "cmd_help.h": "c",
         "wait.h": "c",
-        "__libc__.h": "c",
         "ctype.h": "c",
-        "mmio.h": "c",
         "stdint-gcc.h": "c",
         "acpi.h": "c",
         "assert.h": "c",