build: bump golang base image version to 1.17

[tochicool]

Image fails to build on the current 1.16 tag with the error:

> docker build . --build-arg ARCH=amd64
...
btcd.go:21:2: //go:build comment without // +build comment
The command '/bin/sh -c set -ex   && if [ "${ARCH}" = "amd64" ]; then export GOARCH=amd64; fi   && if [ "${ARCH}" = "arm32v7" ]; then export GOARCH=arm; fi   && if [ "${ARCH}" = "arm64v8" ]; then export GOARCH=arm64; fi   && echo "Compiling for $GOARCH"   && go install -v . ./cmd/...' returned a non-zero code: 1

[coveralls]

Pull Request Test Coverage Report for Build 2984473967

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+16.7%) to 71.86%

---

Files with Coverage Reduction	New Missed Lines	%
btcutil/gcs/gcs.go	1	81.25%

Totals
Change from base Build 2836573928:	16.7%
Covered Lines:	12753
Relevant Lines:	17747

---

💛 - Coveralls

[jcvernaleo]

OK

[coveralls]

Pull Request Test Coverage Report for Build 2984473967

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+0.002%) to 55.131%

---

Files with Coverage Reduction	New Missed Lines	%
btcutil/gcs/gcs.go	1	81.25%

Totals
Change from base Build 2836573928:	0.002%
Covered Lines:	26518
Relevant Lines:	48100

---

💛 - Coveralls