Show diffs for failed tests on i386/Mac OS CI

Seeing the diffs for failed tests in CI is very helpful, especially for developers who
do not have a Mac (or other test platform in question).

Author: alexdowad

azure/i386/test.yml

@@ -17,6 +17,7 @@ steps:
           -j$(/usr/bin/nproc) \
           -g FAIL,XFAIL,BORK,WARN,LEAK,XLEAK,SKIP \
           --offline \
+          --show-diff \
           --show-slow 1000 \
           --set-timeout 120 \
           ${{ parameters.runTestsParameters }}

azure/macos/test.yml

@@ -13,6 +13,7 @@ steps:
           -j$(sysctl -n hw.ncpu) \
           -g FAIL,XFAIL,BORK,WARN,LEAK,XLEAK,SKIP \
           --offline \
+          --show-diff \
           --show-slow 1000 \
           --set-timeout 120 \
           ${{ parameters.runTestsParameters }}