[LNT] Fix rm-machine error reporting

[frederik-h]

Summary

The lnt client tool crashes whenever 'rm-machine' tries to report
an error message after an attempt to remove a non-existing
machine. This is fixed by importing the "http" package instead
of the "http.client" module under the name "http".

[cmatthews]

Sorry, I was reviewing out of order and approved: D79183 which also has a fix for this. I like the test case though, could you commit the test case?

[frederik-h]

In D78632#2013189, @cmatthews wrote:

Sorry, I was reviewing out of order and approved: D79183 which also has a fix for this. I like the test case though, could you commit the test case?

Sorry, I don't have commit access. Could you please commit it for me?

lnt/lnttool/admin.py

     requests = import_module('requests')
     json = import_module('json')
     os = import_module('os')
-    http = import_module('http.client')
+    http = import_module('http')
 
 
 def _error(msg):

tests/lnttool/admin.shtest

 # RM_MACHINE: Deleting runs 1 2 (2/2)
 # RM_MACHINE: Deleted machine localhost__clang_DEV__x86_64:1
 
+! lnt admin rm-machine 42 2> rm_machine2.stderr
+# RUN: FileCheck %s --check-prefix=RM_MACHINE2 < %t.tmp/rm_machine2.stderr
+# RM_MACHINE2: 404: Not Found
+# RM_MACHINE2: Did not find machine '42'
+
 lnt admin list-machines > list_machines2.stdout
 # RUN: FileCheck %s --check-prefix=LIST_MACHINES2 < %t.tmp/list_machines2.stdout
 # LIST_MACHINES2-NOT: localhost__clang_DEV__x86_64:1