[main](backport #3469) Refactor agent version pinning in integration …

…test script (#3476)

* Refactor agent version pinning in integration test script

* remove 8.10.2 version pinning

(cherry picked from commit a7b2514)

# Conflicts:
#	.buildkite/scripts/steps/integration_tests.sh

* resolve cherry-pick conflicts

---------

Co-authored-by: Paolo Chilà <[email protected]>

.buildkite/scripts/steps/integration_tests.sh

@@ -3,12 +3,22 @@ set -euo pipefail
 
 source .buildkite/scripts/common.sh
 
+# Override the agent package version using a string with format <major>.<minor>.<patch>
+# NOTE: use only after version bump when the new version is not yet available, for example:
+# OVERRIDE_AGENT_PACKAGE_VERSION="8.10.3"
+OVERRIDE_AGENT_PACKAGE_VERSION=""
+
+if [[ -n "$OVERRIDE_AGENT_PACKAGE_VERSION" ]]; then
+  OVERRIDE_TEST_AGENT_VERSION=${OVERRIDE_AGENT_PACKAGE_VERSION}"-SNAPSHOT"
+else
+ OVERRIDE_TEST_AGENT_VERSION=""
+fi
 # PACKAGE
-DEV=true EXTERNAL=true SNAPSHOT=true PLATFORMS=linux/amd64,linux/arm64 PACKAGES=tar.gz mage package
+AGENT_PACKAGE_VERSION="${OVERRIDE_AGENT_PACKAGE_VERSION}" DEV=true EXTERNAL=true SNAPSHOT=true PLATFORMS=linux/amd64,linux/arm64 PACKAGES=tar.gz mage package
 
 # Run integration tests
 set +e
-TEST_INTEG_AUTH_ESS_REGION=azure-eastus2 TEST_INTEG_CLEAN_ON_EXIT=true SNAPSHOT=true mage integration:test
+AGENT_VERSION="${OVERRIDE_TEST_AGENT_VERSION}" TEST_INTEG_AUTH_ESS_REGION=azure-eastus2 TEST_INTEG_CLEAN_ON_EXIT=true SNAPSHOT=true mage integration:test
 TESTS_EXIT_STATUS=$?
 set -e