ci-automation: Use run_default_kola_test in easy cases

AWS, Azure, Equinix Metal and GCE vendor tests could easily start
using the default kola test runner function, since they were already
using the run_kola_tests_on_instances function.

ci-automation/vendor-testing/aws.sh

@@ -73,12 +73,4 @@ run_kola_tests() {
 export AWS_ACCESS_KEY_ID
 export AWS_SECRET_ACCESS_KEY
 
-run_kola_tests_on_instances \
-    "${aws_instance_type}" \
-    "${CIA_TAPFILE}" \
-    "${CIA_FIRST_RUN}" \
-    "${more_aws_instance_types[@]}" \
-    '--' \
-    'cl.internet' \
-    '--' \
-    "${@}"
+run_default_kola_tests

ci-automation/vendor-testing/azure.sh

@@ -84,12 +84,4 @@ run_kola_tests() {
       "${@}"
 }
 
-run_kola_tests_on_instances \
-    "${azure_instance_type}" \
-    "${CIA_TAPFILE}" \
-    "${CIA_FIRST_RUN}" \
-    "${other_instance_types[@]}" \
-    '--' \
-    'cl.internet' \
-    '--' \
-    "${@}"
+run_default_kola_tests

ci-automation/vendor-testing/equinix_metal.sh

@@ -59,12 +59,4 @@ run_kola_tests() {
           "${@}"
 }
 
-run_kola_tests_on_instances \
-    "${EQUINIXMETAL_INSTANCE_TYPE}" \
-    "${CIA_TAPFILE}" \
-    "${CIA_FIRST_RUN}" \
-    "${MORE_INSTANCE_TYPES[@]}" \
-    '--' \
-    'cl.internet' \
-    '--' \
-    "${@}"
+run_default_kola_tests

ci-automation/vendor-testing/gce.sh

@@ -76,12 +76,4 @@ run_kola_tests() {
         "${@}"
 }
 
-run_kola_tests_on_instances \
-    "default" \
-    "${CIA_TAPFILE}" \
-    "${CIA_FIRST_RUN}" \
-    "gvnic" \
-    '--' \
-    'cl.internet' \
-    '--' \
-    "${@}"
+run_default_kola_tests