Bumped version of go from 1.16 to 1.17 for dev (#2610)

This is what will be used by the presubmit scripts, and thus using different versions may not clear presubmit checks due to differences in go formatting, mod files, etc.

CHANGELOG.md

@@ -2,7 +2,7 @@
 
 ## HEAD
 
-* Recommended go version for development: 1.16x
+* Recommended go version for development: 1.17x
   * This is the version used by the cloudbuild presubmits. Using a
     different version can lead to presubmits failing due to unexpected
     diffs.

README.md

@@ -69,7 +69,7 @@ The current state of feature implementation is recorded in the
 
 To build and test Trillian you need:
 
- - Go 1.14 or later (go 1.16 matches cloudbuild, and is preferred for developers
+ - Go 1.14 or later (go 1.17 matches cloudbuild, and is preferred for developers
    that will be submitting PRs to this project).
 
 To run many of the tests (and production deployment) you need:

examples/deployment/docker/db_client/Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.16-buster
+FROM golang:1.17-buster
 
 RUN apt-get update && \
     apt-get install -y mariadb-client

examples/deployment/docker/log_server/Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.16-buster as build
+FROM golang:1.17-buster as build
 
 WORKDIR /trillian
 

examples/deployment/docker/log_signer/Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.16-buster as build
+FROM golang:1.17-buster as build
 
 WORKDIR /trillian
 

integration/cloudbuild/testbase/Dockerfile

@@ -1,5 +1,5 @@
 # This Dockerfile builds a base image for Trillan integration tests.
-FROM golang:1.16-buster
+FROM golang:1.17-buster
 
 WORKDIR /testbase