Removed redundant directory in APIs and Services

Bug-AGL: [SPEC-3633]

Signed-off-by: Shankho Boron Ghosh <shankhoghosh123@gmail.com>
Change-Id: Id7ac2ae56db00325df1782d9ec0ab82caebfb0b2
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/documentation/+/25668
Reviewed-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>
Tested-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>

diff --git a/docs/4_APIs_and_Services/4.1_API_Reference/0_api-introduction.md b/docs/4_APIs_and_Services/0_API_Reference.md
similarity index 100%
rename from docs/4_APIs_and_Services/4.1_API_Reference/0_api-introduction.md
rename to docs/4_APIs_and_Services/0_API_Reference.md