Make 'By' translatable in blog posts (#3450)

frappe/website/doctype/blog_post/templates/blog_post.html

@@ -9,7 +9,7 @@
 	<div class="blog-info">
 	<h1 itemprop="headline" class="blog-header">{{ title }}</h1>
 	<p class="post-by text-muted">
-		<a href="/blog?blogger={{ blogger }}" class="no-decoration">By {{ blogger_info and blogger_info.full_name or full_name }}</a>
+		<a href="/blog?blogger={{ blogger }}" class="no-decoration">{{ _("By") }} {{ blogger_info and blogger_info.full_name or full_name }}</a>
 		<i class="blog-dot"></i> {{ frappe.format_date(published_on) }}
 		<i class="blog-dot"></i> <a href="/blog?blog_category={{ blog_category }}" class="no-decoration">{{ category.title }}</a>
 		<i class="blog-dot"></i> {{ comment_text }}

frappe/website/doctype/blog_post/templates/blog_post_row.html

@@ -11,7 +11,7 @@
 			<p class="post-description">{{ post.intro }}</p>
 			<p class="post-by text-muted small">
 				<a href="/blog?blogger={{ post.blogger }}"
-					class="no-decoration">By {{ post.full_name }}</a>
+					class="no-decoration">{{ _("By") }} {{ post.full_name }}</a>
 				<i class="blog-dot"></i> {{ frappe.format_date(post.published_on) }}
 				<i class="blog-dot"></i>
 				<a href="/blog?blog_category={{ post.blog_category }}"
@@ -20,4 +20,4 @@
 			</p>
 		</div>
 	</div>
-</div>
+</div>