Update MCUBoot version to 9e8eddcecba931f99297765779f8b130d808a9a3

Signed-off-by: Sherry Zhang <sherry.zhang2@arm.com>
Change-Id: Ie098089dfd50a1372b08b067d8a68229f350668a
diff --git a/tf-m-code-coverage.yaml b/tf-m-code-coverage.yaml
index 7538249..0b4be2f 100644
--- a/tf-m-code-coverage.yaml
+++ b/tf-m-code-coverage.yaml
@@ -99,7 +99,7 @@
           description: "Name of Jenkins credential for authentication with LAVA."
       - string:
           name: 'MCUBOOT_REFSPEC'
-          default: '74530753b40150080f61cfd9277b1fa7d4e3fa6f'
+          default: '9e8eddcecba931f99297765779f8b130d808a9a3'
           description: |
             Specify which MCUboot version to use
             refs/heads/<branch_name> : Pick up latest HEAD on branch