remove outdated external access rule

[kon-angelo]

How to categorize this PR?

/area control-plane /kind enhancement /platform gcp

What this PR does / why we need it:

Which issue(s) this PR fixes: Fixes #

Special notes for your reviewer:

Release note:

Remove redundant firewall rule `*-allow-external-access` that allowed traffic from all 0

[kon-angelo]

/test

[testmachinery[bot]]

Testrun: e2e-r26sc Workflow: e2e-r26sc-wf Phase: Failed

+---------------------+---------------------+-----------+----------+
|        NAME         |        STEP         |   PHASE   | DURATION |
+---------------------+---------------------+-----------+----------+
| infrastructure-test | infrastructure-test | Failed    | 8m48s    |
| infrastructure-test | infra-flow-test     | Failed    | 9m28s    |
| infrastructure-test | infra-migrate-test  | Failed    | 8m52s    |
| bastion-test        | bastion-test        | Succeeded | 9m48s    |
+---------------------+---------------------+-----------+----------+

[kon-angelo]

/test

[testmachinery[bot]]

Testrun: e2e-mlzp7 Workflow: e2e-mlzp7-wf Phase: Succeeded

+---------------------+---------------------+-----------+----------+
|        NAME         |        STEP         |   PHASE   | DURATION |
+---------------------+---------------------+-----------+----------+
| infrastructure-test | infrastructure-test | Succeeded | 8m43s    |
| infrastructure-test | infra-flow-test     | Succeeded | 7m57s    |
| infrastructure-test | infra-migrate-test  | Succeeded | 8m10s    |
| bastion-test        | bastion-test        | Succeeded | 9m34s    |
+---------------------+---------------------+-----------+----------+

[kon-angelo]

/test

[testmachinery[bot]]

Testrun: e2e-wjshc Workflow: e2e-wjshc-wf Phase: Succeeded

+---------------------+---------------------+-----------+----------+
|        NAME         |        STEP         |   PHASE   | DURATION |
+---------------------+---------------------+-----------+----------+
| bastion-test        | bastion-test        | Succeeded | 9m52s    |
| infrastructure-test | infrastructure-test | Succeeded | 8m38s    |
| infrastructure-test | infra-flow-test     | Succeeded | 8m35s    |
| infrastructure-test | infra-migrate-test  | Succeeded | 8m0s     |
+---------------------+---------------------+-----------+----------+

[kon-angelo]

/invite @ScheererJ

[kon-angelo]

/invite @DockToFuture