Fix cosmetic problems in YAML source

This change corrects problems reported by the `yamllint` linter.

Since key duplication problems were removed in 4d48711, this commit
mainly fixes trailing spaces and extra empty lines at beginning/end of
files.

test/integration/targets/lookups/meta/main.yml

@@ -1,4 +1,3 @@
 dependencies: 
   - prepare_tests
   - prepare_http_tests
-

test/integration/targets/lookups/tasks/main.yml

@@ -22,13 +22,13 @@
   copy: dest={{output_dir}}/foo.txt mode=0644 content="bar"
 
 - name: load the file as a fact
-  set_fact: 
+  set_fact:
     foo: "{{ lookup('file', output_dir + '/foo.txt' ) }}"
 
 - debug: var=foo
 
-- name: verify file lookup 
-  assert: 
+- name: verify file lookup
+  assert:
     that:
         - "foo == 'bar'"
 
@@ -43,7 +43,7 @@
   - "{{output_dir}}/lookup"
 
 - name: create a password file
-  set_fact: 
+  set_fact:
     newpass: "{{ lookup('password', output_dir + '/lookup/password length=8') }}"
 
 - name: stat the password file directory
@@ -143,7 +143,7 @@
 
 - name: get first environment var value
   shell: echo {{ '$' + known_var_name.stdout }}
-  register: known_var_value 
+  register: known_var_value
 
 - name: use env lookup to get known var
   set_fact: