[chore] Add sponsorship assignment requirement (open-telemetry#33299)

As discussed in the collector SIG today, I'm proposing language where
auto-assignment of a sponsor is only a given if the component is
proposed by a member of the project.

.github/ISSUE_TEMPLATE/new_component.yaml

@@ -27,6 +27,7 @@ body:
       description: A vendor-specific component directly interfaces with a vendor-specific API and is expected to be maintained by a representative of the same vendor.
       options:
         - label: This is a vendor-specific component
+        - label: If this is a vendor-specific component, I am a member of the OpenTelemetry organization.
         - label: If this is a vendor-specific component, I am proposing to contribute and support it as a representative of the vendor.
   - type: input
     attributes:

CONTRIBUTING.md

@@ -114,14 +114,22 @@ issue](https://github.com/open-telemetry/opentelemetry-collector-contrib/issues/
 providing the following information:
 
 * Who's the sponsor for your component. A sponsor is an approver or maintainer who will be the official reviewer of the code and a code owner
-  for the component. For vendor-specific components, it is always preferred to find a sponsor. However, if the vendor has not yet contributed
-  a component of the same class (i.e. receiver, processor, exporter, connector, or extension), then a sponsor will be assigned in a
-  round-robin fashion. In all other cases, you will need to find a sponsor for the component in order for it to be accepted.
+  for the component. Generally, you will need to find a sponsor for the component in order for it to be accepted. For vendor-specific
+  components, a sponsor may be assigned under certain circumstances. See additional details below.
 * Some information about your component, such as the reasoning behind it, use-cases, telemetry data types supported, and
   anything else you think is relevant for us to make a decision about accepting the component.
 * The configuration options your component will accept. This will give us a better understanding of what it does, and 
   how it may be implemented.
 
+### Vendor-specific components
+
+A vendor-specific component directly interfaces with a vendor-specific API and is expected to be maintained by a representative of the same vendor.
+It is always preferred to find a sponsor. However in an effort to ensure vendor neutrality, a sponsor will be assigned to a vendor-specific
+component using a round-robin fashion if the following circumstances are met:
+
+1. A member of the OpenTelemetry project proposes to contribute and support the component on behalf of the vendor.
+2. The vendor does not yet have a component of the same class (i.e. receiver, processor, exporter, connector, or extension) in the repository.
+
 Components refer to connectors, exporters, extensions, processors, and receivers. The key criteria to implementing a component is to:
 
 * Implement the [component.Component](https://pkg.go.dev/go.opentelemetry.io/collector/component#Component) interface