Use squiggly heredoc to improve YAML processor specs

spec/lib/gitlab/ci/yaml_processor_spec.rb

@@ -1344,13 +1344,13 @@ module Gitlab
 
         context 'when template is a job' do
           let(:config) do
-            <<EOT
-job1: &JOBTMPL
-  stage: build
-  script: execute-script-for-job
+            <<~EOT
+              job1: &JOBTMPL
+                stage: build
+                script: execute-script-for-job
 
-job2: *JOBTMPL
-EOT
+              job2: *JOBTMPL
+            EOT
           end
 
           it_behaves_like 'job_templates_handling'
@@ -1358,15 +1358,15 @@ EOT
 
         context 'when template is a hidden job' do
           let(:config) do
-            <<EOT
-.template: &JOBTMPL
-  stage: build
-  script: execute-script-for-job
+            <<~EOT
+              .template: &JOBTMPL
+                stage: build
+                script: execute-script-for-job
 
-job1: *JOBTMPL
+              job1: *JOBTMPL
 
-job2: *JOBTMPL
-EOT
+              job2: *JOBTMPL
+            EOT
           end
 
           it_behaves_like 'job_templates_handling'
@@ -1374,18 +1374,18 @@ EOT
 
         context 'when job adds its own keys to a template definition' do
           let(:config) do
-            <<EOT
-.template: &JOBTMPL
-  stage: build
-
-job1:
-  <<: *JOBTMPL
-  script: execute-script-for-job
-
-job2:
-  <<: *JOBTMPL
-  script: execute-script-for-job
-EOT
+            <<~EOT
+              .template: &JOBTMPL
+                stage: build
+
+              job1:
+                <<: *JOBTMPL
+                script: execute-script-for-job
+
+              job2:
+                <<: *JOBTMPL
+                script: execute-script-for-job
+            EOT
           end
 
           it_behaves_like 'job_templates_handling'