Fix the description of `deployments` field in `EnvironmentType` of GraphQL

Problem

Currently, the documentation of deployments field describes as the following:

Deployments of the environment. This field can only be resolved for one project in any single request.

However, this field is belonging to EnvironmentType, so technically for one environment is orthogonal to the implementation.

Proposal

diff --git a/app/graphql/types/environment_type.rb b/app/graphql/types/environment_type.rb
index 2484081a828..dd2286d333d 100644
--- a/app/graphql/types/environment_type.rb
+++ b/app/graphql/types/environment_type.rb
@@ -57,7 +57,7 @@ class EnvironmentType < BaseObject
     field :deployments,
           Types::DeploymentType.connection_type,
           null: true,
-          description: 'Deployments of the environment. This field can only be resolved for one project in any single request.',
+          description: 'Deployments of the environment. This field can only be resolved for one environment in any single request.',
           resolver: Resolvers::DeploymentsResolver do
             extension ::Gitlab::Graphql::Limit::FieldCallCount, limit: 1
           end

Auto-generated message

The following discussion from !95885 (merged) should be addressed:

• @.luke started a discussion:

  Question

  🤔 Is "one project" in this description correct, or should it be "one environment":

            description: 'Deployments of the environment. This field can only be resolved for one environment in any single request.',