templates: use yq's indentation style

[AkihiroSuda]

Fix #1389 so that we can eventually automate updating yamls (#1347) using yq.

Use git show --ignore-all-space --ignore-blank-lines to review this commit.

diff --git a/.yamllint b/.yamllint
index a7c8c3f..20183f4 100644
--- a/.yamllint
+++ b/.yamllint
@@ -3,8 +3,6 @@
 extends: default
 
 rules:
-  indentation:
-    indent-sequences: false
   truthy:
     allowed-values: ['true', 'false', 'on', 'off']
   comments-indentation: disable

[afbjorklund]

Since @jandubois feels strongly about the indentation, I would rather patch go-yaml.

#1389 (comment)

There really should be such a preference in yq, to allow both type of sequence indent...

       prefs := yqlib.NewDefaultYamlPreferences()
       prefs.CompactSequenceIndent = true