fix: pin rust nightly to 1/14/22 to get around rust-lang/rust#93054

Author: kantai

.github/actions/bitcoin-int-tests/Dockerfile.code-cov

@@ -2,7 +2,7 @@ FROM rust:bullseye AS test
 
 WORKDIR /build
 
-RUN rustup override set nightly && \
+RUN rustup override set nightly-2022-01-14 && \
     rustup component add llvm-tools-preview && \
     cargo install grcov
 

.github/actions/bitcoin-int-tests/Dockerfile.generic.bitcoin-tests

@@ -6,7 +6,7 @@ COPY . .
 
 WORKDIR /src/testnet/stacks-node
 
-RUN rustup override set nightly && \
+RUN rustup override set nightly-2022-01-14 && \
     rustup component add llvm-tools-preview && \
     cargo install grcov
 

.github/actions/bitcoin-int-tests/Dockerfile.large-genesis

@@ -9,7 +9,7 @@ RUN cd / && tar -xvzf bitcoin-0.20.0-x86_64-linux-gnu.tar.gz
 
 RUN ln -s /bitcoin-0.20.0/bin/bitcoind /bin/
 
-RUN rustup override set nightly && \
+RUN rustup override set nightly-2022-01-14 && \
     rustup component add llvm-tools-preview && \
     cargo install grcov