vcenter: disable ConfigParser interpolation (#59851)

Password can come with the '%' character. If we keep ConfigParser
interpolation enabled, it will try to modify the value.
Typical error looks like this one:

```
configparser.InterpolationSyntaxError: '%' must be followed by '%' or '(', found: '%Z,sq'
```
See: https://docs.python.org/3/library/configparser.html#interpolation-of-values

test/runner/lib/cloud/vcenter.py

@@ -267,12 +267,12 @@ class VcenterEnvironment(CloudEnvironment):
             # Most of the test cases use ansible_vars, but we plan to refactor these
             # to use env_vars, output both for now
             env_vars = dict(
-                (key.upper(), value) for key, value in parser.items('DEFAULT'))
+                (key.upper(), value) for key, value in parser.items('DEFAULT', raw=True))
 
             ansible_vars = dict(
                 resource_prefix=self.resource_prefix,
             )
-            ansible_vars.update(dict(parser.items('DEFAULT')))
+            ansible_vars.update(dict(parser.items('DEFAULT', raw=True)))
 
         else:
             env_vars = dict(