Description of problem:
OperatorSDK run bundle generate the catalogsource without the "HTTP-PROXY" if the cluster configed with the "HTTP-PROXY". And the catalogsource pod can't be built success. 

Version-Release number of selected component (if applicable):
operator-sdk version: "v1.8.0-ocp", commit: "016423f32c9757a10dc7a9e953818bc20ae3eba4", kubernetes version: "v1.20.2", go version: "go1.16.5", GOOS: "linux", GOARCH: "amd64"
cv:4.8.0-0.nightly-2021-06-19-005119

How reproducible:
always

Steps to Reproduce:
1.install one disconnected cluster with HTTP-PROXY
2.run operator-sdk run bundle (image from the network)
$operator-sdk run bundle quay.io/xxxx/blacklist-xxxxle:v4.8

Actual results:
The catalogsource pods failed at download the image "quay.io/xxxx/blacklist-xxxxle:v4.8" without the HTTP-PROXY config.

`time="2021-06-22T06:50:23Z" level=info msg="adding to the registry" bundles="[quay.io/xxxx/blacklist-xxxxle:v4.8]"
time="2021-06-22T06:50:54Z" level=error msg="permissive mode disabled" bundles="[quay.io/olmqe/blacklist-bundle:v4.8]" error="[error resolving name : failed to do request: Head \"https://quay.io/v2/xxxx/blacklist-xxxxle/manifests/v4.8\": dial tcp 3.213.173.170:443: i/o timeout, image \"quay.io/xxxx/blacklist-xxxxle:v4.8\": not found]"
Error: [error resolving name : failed to do request: Head "https://quay.io/v2/xxxx/blacklist-xxxxle/manifests/v4.8": dial tcp 3.213.173.170:443: i/o timeout, image "quay.io/xxxx/blacklist-xxxxle:v4.8": not found]`

Expected results:
The pod of catalogsource should add the cluster HTTP-PROXY automatically.
- name: HTTP_PROXY
      value: http://proxy-user1:JYgUxxxx4PXJbxJK@ec2-18-xxxx10-203.us-east-2.compute.amazonaws.com:3128
    - name: HTTPS_PROXY
      value: http://proxy-user1:JYgUxxxx4DY4PXJbxJK@ec2-18-xxxx10-203.us-east-2.compute.amazonaws.com:3128
    - name: NO_PROXY
      value: .cluster.local,.svc,.us-east-2.compute.internal,10.0.0.0/16,10.128.0.0/14,127.0.xxxx.254.xxxx172.30.0.0/16,xxxxi-int.wewanxxxxevcluster.openshift.com,localhoxxxxst.no-proxy.com


Additional info: