Rerun mage fmt update for metricbeat

[kaiyan-sheng]

CI is failing because Error: some files are not up-to-date. Run 'mage fmt update' then review and commit the changes. Modified: [metricbeat/docs/modules/haproxy.asciidoc]

[ChrsMark]

Lgtm

[kaiyan-sheng]

CI still failing because of a separate issue:

--- FAIL: TestFetch (90.45s)
    node_integration_test.go:37: 
        	Error Trace:	node_integration_test.go:37
        	Error:      	Should NOT be empty, but was []
        	Test:       	TestFetch
panic: runtime error: index out of range [0] with length 0 [recovered]
	panic: runtime error: index out of range [0] with length 0
goroutine 21 [running]:
testing.tRunner.func1(0xc0000f9800)
	/usr/local/go/src/testing/testing.go:874 +0x3a3
panic(0xdbe480, 0xc000305260)
	/usr/local/go/src/runtime/panic.go:679 +0x1b2
github.com/elastic/beats/x-pack/metricbeat/module/redisenterprise/node.TestFetch(0xc0000f9800)
	/go/src/github.com/elastic/beats/x-pack/metricbeat/module/redisenterprise/node/node_integration_test.go:38 +0x6fc
testing.tRunner(0xc0000f9800, 0xe3fda0)
	/usr/local/go/src/testing/testing.go:909 +0xc9
created by testing.(*T).Run
	/usr/local/go/src/testing/testing.go:960 +0x350
FAIL	github.com/elastic/beats/x-pack/metricbeat/module/redisenterprise/node	90.461s
=== RUN   TestFetch
--- FAIL: TestFetch (89.06s)
    proxy_integration_test.go:37: 
        	Error Trace:	proxy_integration_test.go:37
        	Error:      	Should NOT be empty, but was []
        	Test:       	TestFetch
panic: runtime error: index out of range [0] with length 0 [recovered]
	panic: runtime error: index out of range [0] with length 0
goroutine 8 [running]:
testing.tRunner.func1(0xc0000d5800)
	/usr/local/go/src/testing/testing.go:874 +0x3a3
panic(0xdbe480, 0xc0002fe980)
	/usr/local/go/src/runtime/panic.go:679 +0x1b2
github.com/elastic/beats/x-pack/metricbeat/module/redisenterprise/proxy.TestFetch(0xc0000d5800)
	/go/src/github.com/elastic/beats/x-pack/metricbeat/module/redisenterprise/proxy/proxy_integration_test.go:38 +0x6fc
testing.tRunner(0xc0000d5800, 0xe3fda8)
	/usr/local/go/src/testing/testing.go:909 +0xc9
created by testing.(*T).Run
	/usr/local/go/src/testing/testing.go:960 +0x350
FAIL	github.com/elastic/beats/x-pack/metricbeat/module/redisenterprise/proxy	89.080s
FAIL
FAILURES:
Package: github.com/elastic/beats/x-pack/metricbeat/module/redisenterprise/node
Test:    TestFetch
Error Trace:	proxy_integration_test.go:37
panic: runtime error: index out of range [0] with length 0 [recovered]