Run external tools directly

[cipherboy]

Switch to running external tools directly

Rather than expecting them to be installed locally (via a previous
go get operation outside of the repo), use the go run ...@latest
pattern. This will download the package (the first time), but not
necessarily install it for the user on a $PATH-visible location.

This has the added side effect of ensuring everyone is on the same
version.

---

Also runs make fmt to fix a few blank lines.

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In particular, on a fresh system with no dependencies, running make bootstrap fails for me with:

Installing/Updating golang.org/x/tools/cmd/goimports
go: modules disabled by GO111MODULE=off; see 'go help modules'
Installing/Updating github.com/golangci/revgrep/cmd/revgrep
go: modules disabled by GO111MODULE=off; see 'go help modules'
Installing/Updating mvdan.cc/gofumpt
go: modules disabled by GO111MODULE=off; see 'go help modules'
Installing/Updating honnef.co/go/tools/cmd/staticcheck
go: modules disabled by GO111MODULE=off; see 'go help modules'
make: *** [Makefile:168: .ci-bootstrap] Error 1

This is because this hack:

# bootstrap the build by downloading additional tools needed to build
ci-bootstrap: .ci-bootstrap
.ci-bootstrap:
    @for tool in  $(EXTERNAL_TOOLS_CI) ; do \
        echo "Installing/Updating $$tool" ; \
        GO111MODULE=off $(GO_CMD) get -u $$tool; \
    done
    @touch .ci-bootstrap

doesn't work on Go 1.22+ apparently: https://tip.golang.org/doc/go1.22#go-command