[Snyk] Security upgrade golang from 1.18.6 to 1.20.1 (#149)

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-DEBIAN11-CURL-3065656
- https://snyk.io/vuln/SNYK-DEBIAN11-GIT-3051727
- https://snyk.io/vuln/SNYK-DEBIAN11-GIT-3232722
- https://snyk.io/vuln/SNYK-DEBIAN11-GIT-3232724
- https://snyk.io/vuln/SNYK-DEBIAN11-LIBTASN16-3061097

Co-authored-by: snyk-bot <snyk-bot@snyk.io>

Dockerfile

@@ -1,6 +1,6 @@
 # This dockerfile is used to run unit tests.
 
-FROM golang:1.18.6
+FROM golang:1.20.1
 
 # install redis
 RUN git clone -b 5.0 --depth 1 https://github.com/antirez/redis.git