Fix #21406: Hide repo information from file view/blame mode (#21420)

# Summary

The repo information such as description, stats and topics are getting
displayed in the top-bar when viewing a file. This has been fixed to
display the repo information only while navigating the repo and not
while viewing or blaming a file from the repo

## Before fix

Screenshot from the issue


![image](https://user-images.githubusercontent.com/47709856/195278543-9afbb735-7bd3-4f42-b3ba-da514c6989d2.png)

## After the fix

- **Repo homepage**

The repo description, topics and summary will be displayed


![image](https://user-images.githubusercontent.com/47709856/195443913-2ca967cd-6694-4a97-98d0-4d0750692b5d.png)

- **When opening a file**

The repo description, topic and summary has been conditionally hidden
from the view

<img width="1311" alt="image"
src="https://user-images.githubusercontent.com/47709856/195278964-9479231c-62ad-4c0e-b438-2018f22289db.png">

- **When running blame on a file**

> This was originally not part of the issue #21406. However the fix
seems relevant for the blame view as well.

<img width="1312" alt="image"
src="https://user-images.githubusercontent.com/47709856/195279619-02010775-aec3-4c8d-a184-d2d838c797e8.png">

- **From within a directory**

The repo description, topics and summary will not be displayed


![image](https://user-images.githubusercontent.com/47709856/195444080-ff5b2def-7e0f-47d7-b54a-7e9df5f9edd8.png)


Supporting integration tests have also been added.

templates/repo/home.tmpl

@@ -3,6 +3,7 @@
 	{{template "repo/header" .}}
 	<div class="ui container {{if .IsBlame}}fluid padded{{end}}">
 		{{template "base/alert" .}}
+		{{if and (not .HideRepoInfo) (not .IsBlame)}}
 		<div class="ui repo-description">
 			<div id="repo-desc">
 				{{$description := .Repository.DescriptionHTML $.Context}}
@@ -31,6 +32,7 @@
 		{{range .Topics}}<a class="ui repo-topic large label topic" href="{{AppSubUrl}}/explore/repos?q={{.Name}}&topic=1">{{.Name}}</a>{{end}}
 		{{if and .Permission.IsAdmin (not .Repository.IsArchived)}}<a id="manage_topic" class="muted">{{.locale.Tr "repo.topic.manage_topics"}}</a>{{end}}
 		</div>
+		{{end}}
 		{{if and .Permission.IsAdmin (not .Repository.IsArchived)}}
 		<div class="ui repo-topic-edit grid form" id="topic_edit" style="display:none">
 			<div class="fourteen wide column">

templates/repo/sub_menu.tmpl

@@ -1,3 +1,4 @@
+{{if and (not .HideRepoInfo) (not .IsBlame)}}
 <div class="ui segments repository-summary{{if and (.Permission.CanRead $.UnitTypeCode) (not .IsEmptyRepo) .LanguageStats}} repository-summary-language-stats{{end}} mt-2 mb-0">
 	<div class="ui segment sub-menu repository-menu">
 		<div class="ui two horizontal center link list">
@@ -44,3 +45,4 @@
 	</a>
 	{{end}}
 </div>
+{{end}}