fix indentation

Author: rustagir

source/aggregation.txt

@@ -78,9 +78,9 @@ Consider the following limitations when performing aggregation operations:
 
   .. important:: $graphLookup Exception
 
-	 The :manual:`$graphLookup
-	 </reference/operator/aggregation/graphLookup/>` stage has a strict
-	 memory limit of 100 megabytes and ignores the ``allowDiskUse`` option.
+     The :manual:`$graphLookup
+     </reference/operator/aggregation/graphLookup/>` stage has a strict
+     memory limit of 100 megabytes and ignores the ``allowDiskUse`` option.
 
 .. _php-aggregation-example:
 
@@ -111,20 +111,20 @@ of New York. To do so, it uses an aggregation pipeline that contains the followi
    :copyable:
 
    .. input:: /includes/aggregation/aggregation.php
-	  :start-after: start-match-group
-	  :end-before: end-match-group
-	  :language: php
-	  :dedent:
+      :start-after: start-match-group
+      :end-before: end-match-group
+      :language: php
+      :dedent:
 
    .. output:: 
-	  :visible: false
+      :visible: false
 
-	  {"_id":"Brooklyn","count":173}
-	  {"_id":"Queens","count":204}
-	  {"_id":"Bronx","count":71}
-	  {"_id":"Staten Island","count":20}
-	  {"_id":"Missing","count":2}
-	  {"_id":"Manhattan","count":221}
+      {"_id":"Brooklyn","count":173}
+      {"_id":"Queens","count":204}
+      {"_id":"Bronx","count":71}
+      {"_id":"Staten Island","count":20}
+      {"_id":"Missing","count":2}
+      {"_id":"Manhattan","count":221}
 
 Explain an Aggregation
 ~~~~~~~~~~~~~~~~~~~~~~
@@ -147,19 +147,19 @@ from the preceding :ref:`php-aggregation-example`:
    :copyable:
 
    .. input:: /includes/aggregation/aggregation.php
-	  :start-after: start-explain
-	  :end-before: end-explain
-	  :language: php
-	  :dedent:
-
-   .. output:: 
-	  :visible: false
-
-	  {"explainVersion":"2","queryPlanner":{"namespace":"sample_restaurants.restaurants",
-	  "indexFilterSet":false,"parsedQuery":{"cuisine":{"$eq":"Bakery"}},"queryHash":"865F14C3",
-	  "planCacheKey":"D56D6F10","optimizedPipeline":true,"maxIndexedOrSolutionsReached":false,
-	  "maxIndexedAndSolutionsReached":false,"maxScansToExplodeReached":false,"winningPlan":{
-	  ... }
+      :start-after: start-explain
+      :end-before: end-explain
+      :language: php
+      :dedent:
+
+   .. output::
+      :visible: false
+
+      {"explainVersion":"2","queryPlanner":{"namespace":"sample_restaurants.restaurants",
+      "indexFilterSet":false,"parsedQuery":{"cuisine":{"$eq":"Bakery"}},"queryHash":"865F14C3",
+      "planCacheKey":"D56D6F10","optimizedPipeline":true,"maxIndexedOrSolutionsReached":false,
+      "maxIndexedAndSolutionsReached":false,"maxScansToExplodeReached":false,"winningPlan":{
+      ... }
 
 Additional Information
 ----------------------