Kill all Sidechain renBTC gauges

Gauge Proposals
#1

Summary:

This proposal is to kill all remaining gauges containing renBTC. This includes pools on Arbitrum, Fantom, Polygon, and Avalanche.

References/Useful links:

Arbitrum WBTC/renBTC pool: https://curve.fi/#/arbitrum/pools/ren/deposit
Arbitrum gauge: https://etherscan.io/address/0xDB3fd1bfC67b5D4325cb31C04E0Cae52f1787FD6#code

Fantom WBTC/renBTC pool: https://curve.fi/#/fantom/pools/ren/deposit
Fantom gauge: https://etherscan.io/address/0xbc38bd19227f91424ed4132f630f51c9a42fa338

Polygon WBTC/renBTC pool: https://curve.fi/#/polygon/pools/ren/deposit
Polygon gauge: https://etherscan.io/address/0x8d9649e50a0d1da8e939f800fb926cde8f18b47d

Avalanche WBTC.e/renBTC pool: https://curve.fi/#/avalanche/pools/ren/deposit
Avalanche gauge: https://etherscan.io/address/0x00f7d467ef51e44f11f52a0c0bef2e56c271b264

Motivation:

Ren protocol has previously stated support for their renBTC bridge may be discontinued in the near future, these Curve gauges on sidechains/L2s are still active. These pools no longer require incentives.