Update for private link feature

[bowen0106]

• Add Get/List operation for private endpoint connection sub resource in private link service.
• Add proxy protocol support in private link service and private endpoint connection.

Latest improvements:

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[azuresdkci]

Can one of the admins verify this patch?

[AutorestCI]

Automation for azure-sdk-for-python

Encountered a Subprocess error: (azure-sdk-for-python)

Command: ['/usr/local/bin/autorest', '/tmp/tmpxfswj5gi/rest/specification/network/resource-manager/readme.md', '--keep-version-file', '--multiapi', '--no-async', '--python', '--python-mode=update', '--python-sdks-folder=/tmp/tmpxfswj5gi/sdk/sdk', '--use=@microsoft.azure/autorest.python@4.0.70', '--version=preview']
Finished with return code -6
and output:

AutoRest code generation utility [version: 2.0.4283; node: v10.15.3]
(C) 2018 Microsoft Corporation.
https://aka.ms/autorest
   Loading AutoRest core      '/root/.autorest/@microsoft.azure_autorest-core@2.0.4405/node_modules/@microsoft.azure/autorest-core/dist' (2.0.4405)
   Loading AutoRest extension '@microsoft.azure/autorest.python' (4.0.70->4.0.70)
   Loading AutoRest extension '@microsoft.azure/autorest.modeler' (2.3.44->2.3.44)
Processing batch task - {"tag":"package-2019-09"} .

<--- Last few GCs --->

[32489:0x33f1cc0]   111019 ms: Mark-sweep 1372.1 (1425.2) -> 1371.8 (1425.7) MB, 1940.8 / 0.0 ms  (average mu = 0.114, current mu = 0.002) allocation failure scavenge might not succeed
[32489:0x33f1cc0]   113075 ms: Mark-sweep 1372.6 (1425.7) -> 1372.3 (1426.2) MB, 2052.5 / 0.0 ms  (average mu = 0.061, current mu = 0.002) allocation failure scavenge might not succeed


<--- JS stacktrace --->

==== JS stack trace =========================================

    0: ExitFrame [pc: 0x26762ecdbe1d]
Security context: 0x2a87ae51e6e9 <JSObject>
    1: ParseNodeInternal(aka ParseNodeInternal) [0x11a7fd641441] [/root/.autorest/@microsoft.azure_autorest-core@2.0.4405/node_modules/@microsoft.azure/autorest-core/dist/lib/ref/yaml.js:~86] [pc=0x26762f2a1f7f](this=0x219d93c026f1 <undefined>,yamlRootNode=0x20159a682a81 <Object map = 0x3d45871319b1>,yamlNode=0x2a1cf30714e1 <Object map = 0x2066ae2f3119>,onEr...

FATAL ERROR: Ineffective mark-compacts near heap limit Allocation failed - JavaScript heap out of memory
 1: 0x8dc510 node::Abort() [node]
 2: 0x8dc55c  [node]
 3: 0xad9b5e v8::Utils::ReportOOMFailure(v8::internal::Isolate*, char const*, bool) [node]
 4: 0xad9d94 v8::internal::V8::FatalProcessOutOfMemory(v8::internal::Isolate*, char const*, bool) [node]
 5: 0xec7bf2  [node]
 6: 0xec7cf8 v8::internal::Heap::CheckIneffectiveMarkCompact(unsigned long, double) [node]
 7: 0xed3dd2 v8::internal::Heap::PerformGarbageCollection(v8::internal::GarbageCollector, v8::GCCallbackFlags) [node]
 8: 0xed4704 v8::internal::Heap::CollectGarbage(v8::internal::AllocationSpace, v8::internal::GarbageCollectionReason, v8::GCCallbackFlags) [node]
 9: 0xed7371 v8::internal::Heap::AllocateRawWithRetryOrFail(int, v8::internal::AllocationSpace, v8::internal::AllocationAlignment) [node]
10: 0xea07f4 v8::internal::Factory::NewFillerObject(int, bool, v8::internal::AllocationSpace) [node]
11: 0x114018e v8::internal::Runtime_AllocateInNewSpace(int, v8::internal::Object**, v8::internal::Isolate*) [node]
12: 0x26762ecdbe1d

[AutorestCI]

Automation for azure-sdk-for-go

A PR has been created for you:
Azure/azure-sdk-for-go#6039

[anton-evseev]

@KrisBash please take a look

[KrisBash]

LGTM