Fix/issue 855 - TGW routes

[fredbonin]

Fixed the issue by inserting the TGW local name in the construct name for associations.

I did not use the remote TGW name as mentioned here #855 since it might lead to collision : name would be tgw_associate_Main_core and tgw_associate_Main_core if 2 TGWs want to target Main TGW for the save core route.

With the TGW local name, it works : tgw_associate_TGW2_core and tgw_associate_TGW3_core

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[Brian969]

PR is NOT working per design:

• To test, requires a TGW in 3 regions (ca-central-1, us-east-1, and us-west-1)
• Everything works fine with 2 TGW's (ca-central-1, us-east-1)
• adding the 3 TGW works fine without an attachment/associations:
  • but obviously not usable

          {
            "name": "West",
            "asn": 64555,
            "region": "us-west-1",
            "features": {
              "DNS-support": true,
              "VPN-ECMP-support": true,
              "Default-route-table-association": false,
              "Default-route-table-propagation": false,
              "Auto-accept-sharing-attachments": true
            },
            "route-tables": ["core-w", "segregated-w", "shared-w", "standalone-w"],
            "tgw-routes": []
          }

• adding JUST an attachment, the peering connection is never approved
  • while this SM succeeds, if a rt-association had been included, it would have failed the SM waiting for approval

          {
            "name": "West",
            "asn": 64555,
            "region": "us-west-1",
            "features": {
              "DNS-support": true,
              "VPN-ECMP-support": true,
              "Default-route-table-association": false,
              "Default-route-table-propagation": false,
              "Auto-accept-sharing-attachments": true
            },
            "route-tables": ["core-w", "segregated-w", "shared-w", "standalone-w"],
            "tgw-attach": {
              "associate-to-tgw": "Main",
              "account": "shared-network",
              "region": "${HOME_REGION}",
              "tgw-rt-associate-local": [],
              "tgw-rt-associate-remote": []
            },
            "tgw-routes": []
          }

• If we manually approve the peering connection, change config to, and rerun SM:

              "tgw-rt-associate-local": ["core-w"],
              "tgw-rt-associate-remote": ["shared"]

• SM succeeds, BUT, it DROPS the east to central tgw association, when it creates the West to central tgw association
• PR needs reworking.

[archikierstead]

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