.github/workflows/go.yml: bump minimum Go version to 1.13

1.12 is now EOL for almost 2 years: https://endoflife.date/go.

Signed-off-by: Mateusz Gozdek <[email protected]>

Author: invidian

.github/workflows/go.yml

@@ -11,7 +11,7 @@ permissions:
 
 env:
   # Minimum supported Go toolchain
-  ACTION_MINIMUM_TOOLCHAIN: "1.12"
+  ACTION_MINIMUM_TOOLCHAIN: "1.13"
 
 jobs:
   build: