chore: tagRelease.sh: bump to 1.6.4 in release-1.6 branch [skip-build] (#1334)

Signed-off-by: RHDH Build (rhdh-bot) <[email protected]>

Author: rhdh-bot

artifacts/attributes.adoc

@@ -13,8 +13,8 @@
 :product-local: Red Hat Developer Hub Local
 :product-local-very-short: RHDH Local
 :product-version: 1.6
-:product-bundle-version: 1.6.3
-:product-chart-version: 1.6.3
+:product-bundle-version: 1.6.4
+:product-chart-version: 1.6.4
 :product-backstage-version: 1.36.1
 :product-version-next: 1.7
 :product-custom-resource-type: Backstage