fix(x-pack/winlogbeat powershell dashboard): typos (#34331)

Fix a type in the title of the PowerShell overview dashboard.

Refer to "PowerShell" instead of "powershell" for consistency with the product name.

---------

Signed-off-by: Agnivesh Chaubey <agniveshvapi@gmail.com>
Co-authored-by: Andrew Kroh <andrew.kroh@elastic.co>

x-pack/winlogbeat/module/powershell/_meta/kibana/7/dashboard/c77e06c0-9e7c-11ea-af6f-cfdb1ee1d6c8.json

@@ -1,6 +1,6 @@
 {
     "attributes": {
-        "description": "Overview dashboard por powershell module.",
+        "description": "Overview dashboard for PowerShell module.",
         "hits": 0,
         "kibanaSavedObjectMeta": {
             "searchSourceJSON": {
@@ -306,7 +306,7 @@
             }
         ],
         "timeRestore": false,
-        "title": "[Winlogbeat powershell] Overview",
+        "title": "[Winlogbeat PowerShell] Overview",
         "version": 1
     },
     "coreMigrationVersion": "8.8.0",