Fix logging for HostGA plugin retry logic

[pgombar]

Description

• Change info to periodic, otherwise it will show up every 3 seconds.

• Remove successful log message since it's too frequent and we don't usually log successes, only failures.

Issue #1653

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##             release-2.2.43    #1655   +/-   ##
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Impacted Files	Coverage Δ
azurelinuxagent/common/protocol/wire.py	75.43% <100%> (ø)

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[larohra]

Make this verbose maybe?

[pgombar]

I thought about that, but seeing that our approach for everything else is to log only in case of failures, it didn't make sense to keep it.

[pgombar]

The restutil class actually already reports HTTP response codes to the verbose log:

2019/10/03 14:19:03.577846 INFO ExtHandler Using host plugin as default channel
2019/10/03 14:19:03.577928 VERBOSE ExtHandler Fetch [http://168.63.129.16:32526/extensionArtifact] with headers [{'x-ms-containerid': u'7046131f-09e6-49a7-94d0-046fecde7b31', 'x-ms-version': '2015-09-01', 'x-ms-host-config-name': u'2168188a-b556-4cbe-bd34-0c2ee61b05c9.0.2168188a-b556-4cbe-bd34-0c2ee61b05c9.0._Publisher-8.1.0.195.1.xml', 'x-ms-artifact-location': u'https://md-rbpdn51z1wb2.blob.core.windows.net/$system/Publisher-8.1.0.195.4c6f8a03-61a5-49b8-ad66-b2aeb63ad93f.vmSettings?sv=2017-04-17&sr=b&sk=system-1&sig=K%2bbjPdHEKIq8oZ6U6tzbW2S4UxSgnD3g0s6uunZ865Q%3d&se=9999-01-01T00%3a00%3a00Z&sp=r'}]
2019/10/03 14:19:03.578215 VERBOSE ExtHandler HTTP connection [GET] [/extensionArtifact] [None] [{'x-ms-containerid': u'7046131f-09e6-49a7-94d0-046fecde7b31', 'x-ms-version': '2015-09-01', 'x-ms-host-config-name': u'2168188a-b556-4cbe-bd34-0c2ee61b05c9.0.2168188a-b556-4cbe-bd34-0c2ee61b05c9.0._Publisher-8.1.0.195.1.xml', 'x-ms-artifact-location': u'https://md-rbpdn51z1wb2.blob.core.windows.net/$system/Publisher-8.1.0.195.4c6f8a03-61a5-49b8-ad66-b2aeb63ad93f.vmSettings?sv=2017-04-17&sr=b&sk=system-1&sig=K%2bbjPdHEKIq8oZ6U6tzbW2S4UxSgnD3g0s6uunZ865Q%3d&se=9999-01-01T00%3a00%3a00Z&sp=r', 'User-Agent': 'WALinuxAgent/2.2.43', 'Connection': 'close'}]
2019/10/03 14:19:03.589926 VERBOSE ExtHandler [HTTP Response] Status Code 200
2019/10/03 14:19:03.590171 INFO ExtHandler Request succeeded using the host plugin channel.

Since we already have [HTTP Response] Status Code 200 the next message is unnecessary.

[larohra]

Minor comment else LGTM