build: Bump MSRV to 1.83.0

The dependency `bitfield-struct` 0.10.x of `igvm` 0.3.5 requires MSRV
1.83.0, bump to catch up.

Update image to 20250412-0 because MSRV in Dockerfile is updated.

Signed-off-by: Ruoqing He <heruoqing@iscas.ac.cn>

.github/workflows/release.yaml

@@ -45,7 +45,7 @@ jobs:
           target: ${{ matrix.platform.target }}
           args: ${{ matrix.platform.args  }}
           strip: true
-          toolchain: "1.82.0"
+          toolchain: "1.83.0"
       - name: Copy Release Binaries
         if: github.event_name == 'create' && github.event.ref_type == 'tag'
         shell: bash