Rename "People" to "Members" in organization page and use a better icon (#22960)

`member` is how it's named in the code

Closes #22931 

Before | After
--- | ---

![image](https://user-images.githubusercontent.com/20454870/219781155-69a8476e-0f04-4b70-bda5-ea6fa8ce676c.png)
|
![image](https://user-images.githubusercontent.com/20454870/219780887-61644c27-36a2-4e1f-8f98-be3911883b49.png)

---------

Signed-off-by: Yarden Shoham <hrsi88@gmail.com>
Co-authored-by: delvh <leon@kske.dev>

templates/org/home.tmpl

@@ -42,7 +42,7 @@
 					<div class="ui divider"></div>
 				{{end}}
 				<h4 class="ui top attached header gt-df">
-					<strong class="gt-f1">{{.locale.Tr "org.people"}}</strong>
+					<strong class="gt-f1">{{.locale.Tr "org.members"}}</strong>
 					<div class="ui">
 						<a class="text grey gt-dif gt-ac" href="{{.OrgLink}}/members"><span>{{.MembersTotal}}</span> {{svg "octicon-chevron-right"}}</a>
 					</div>

templates/org/menu.tmpl

@@ -18,7 +18,7 @@
 		{{end}}
 		{{if .IsOrganizationMember}}
 			<a class="{{if $.PageIsOrgMembers}}active {{end}}item" href="{{$.OrgLink}}/members">
-				{{svg "octicon-organization"}}&nbsp;{{$.locale.Tr "org.people"}}
+				{{svg "octicon-person"}}&nbsp;{{$.locale.Tr "org.members"}}
 				{{if .NumMembers}}
 					<div class="ui primary label">{{.NumMembers}}</div>
 				{{end}}

templates/user/overview/header.tmpl

@@ -39,7 +39,7 @@
 			{{if .ContextUser.IsOrganization}}
 				{{if .IsOrganizationMember}}
 					<a class="item" href="{{$.OrgLink}}/members">
-						{{svg "octicon-organization"}}&nbsp;{{$.locale.Tr "org.people"}}
+						{{svg "octicon-person"}}&nbsp;{{$.locale.Tr "org.members"}}
 						{{if .NumMembers}}
 							<div class="ui primary label">{{.NumMembers}}</div>
 						{{end}}