tests: consolidate test config into nextest profiles

Centralize test configuration (filters, retries, fail-fast,
sequential/parallel scheduling) into nextest profiles, replacing
scattered flags across shell scripts. This simplifies the scripts
and provides a single source of truth for test behavior.

Enable JUnit XML output per profile, giving CI systems structured
test results for better reporting.

Not all test invocations are converted to profiles yet. Just the
ones that are repeated across scripts.

Signed-off-by: Anirudh Rayabharam <anrayabh@microsoft.com>

scripts/common-aarch64.sh

@@ -3,6 +3,7 @@
 WORKLOADS_DIR="$HOME/workloads"
 
 mkdir -p "$WORKLOADS_DIR"
+mkdir -p "$WORKLOADS_DIR/junit"
 
 build_edk2() {
     EDK2_BUILD_DIR="$WORKLOADS_DIR/edk2_build"