ci(gcb): Drop Docker version to 19.03.8 as that's the latest on GCB

Author: BYK

README.md

@@ -4,7 +4,7 @@ Official bootstrap for running your own [Sentry](https://sentry.io/) with [Docke
 
 ## Requirements
 
- * Docker 19.03.12+
+ * Docker 19.03.8+
  * Compose 1.24.1+
 
 ## Minimum Hardware Requirements:

install.sh

@@ -11,7 +11,7 @@ dcr="$dc run --rm"
 log_file="sentry_install_log-`date +'%Y-%m-%d_%H-%M-%S'`.txt"
 exec &> >(tee -a "$log_file")
 
-MIN_DOCKER_VERSION='19.03.12'
+MIN_DOCKER_VERSION='19.03.8'
 MIN_COMPOSE_VERSION='1.24.1'
 MIN_RAM=2400 # MB