Fix "description:" field for affected jobs

Was written as "Description:" and didn't have effect.

Also, fix typos /e laborate descriptions where applicable.

Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
Change-Id: I92973abdd892fc5d41e42a9ddafbd5d123544450
diff --git a/tf-a-builder.yaml b/tf-a-builder.yaml
index 601e36a..4b04c9b 100644
--- a/tf-a-builder.yaml
+++ b/tf-a-builder.yaml
@@ -5,7 +5,7 @@
     concurrent: true
     disabled: false
     defaults: global
-    Description: |
+    description: |
       Trusted Firmware A (TF-A) builder
     properties:
         - build-discarder: