fix: remove extra closing parenthesis in sub-config error (#10479)

#### Description

Removed an extra closing parenthesis. This corrects the formatting of
the error message for unexpected sub-config value kinds.

Found in:
https://github.com/open-telemetry/opentelemetry-collector-contrib/pull/33268/files#diff-9137db5fde5eb0d6870425c0023cec1a5bdfe92f58f8a72e278b55635afc6e95R48

Author: rogercoll

.chloggen/fix_error_format.yaml

@@ -0,0 +1,25 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: 'enhancement'
+
+# The name of the component, or a single word describing the area of concern, (e.g. otlpreceiver)
+component: confmap
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Remove extra closing parenthesis in sub-config error
+
+# One or more tracking issues or pull requests related to the change
+issues: [10480]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

confmap/confmap.go

@@ -137,7 +137,7 @@ func (l *Conf) Sub(key string) (*Conf, error) {
 		return NewFromStringMap(v), nil
 	}
 
-	return nil, fmt.Errorf("unexpected sub-config value kind for key:%s value:%v kind:%v)", key, data, reflect.TypeOf(data).Kind())
+	return nil, fmt.Errorf("unexpected sub-config value kind for key:%s value:%v kind:%v", key, data, reflect.TypeOf(data).Kind())
 }
 
 // ToStringMap creates a map[string]any from a Parser.