Remove deprecate action

https://old.reddit.com/r/rust/comments/vyx4oj/actionsrs_organization_became_unmaintained/

Looking at this holistically, I don't fully understand *why* we need an
action here? Seems like we can just use rustup? nowadays github runners
come with rustup pre-installed.

.github/workflows/ci.yaml

@@ -17,6 +17,10 @@ env:
   RUSTFLAGS: "-D warnings -W unreachable-pub -W rust-2021-compatibility"
   RUSTUP_MAX_RETRIES: 10
 
+defaults:
+  run:
+    shell: bash
+
 jobs:
   rust:
     if: github.repository == 'rust-lang/rust-analyzer'

.github/workflows/metrics.yaml

@@ -10,6 +10,10 @@ env:
   RUSTFLAGS: "-D warnings -W unreachable-pub"
   RUSTUP_MAX_RETRIES: 10
 
+defaults:
+  run:
+    shell: bash
+
 jobs:
   metrics:
     if: github.repository == 'rust-lang/rust-analyzer'

.github/workflows/publish.yml

@@ -9,6 +9,10 @@ on:
     branches:
       - release
 
+defaults:
+  run:
+    shell: bash
+
 jobs:
   publish:
     name: publish

.github/workflows/release.yaml

@@ -19,6 +19,10 @@ env:
   MACOSX_DEPLOYMENT_TARGET: 10.15
   CARGO_TARGET_AARCH64_UNKNOWN_LINUX_GNU_LINKER: aarch64-linux-gnu-gcc
 
+defaults:
+  run:
+    shell: bash
+
 jobs:
   dist:
     strategy:

.github/workflows/rustdoc.yaml

@@ -10,6 +10,10 @@ env:
   RUSTFLAGS: "-D warnings -W unreachable-pub"
   RUSTUP_MAX_RETRIES: 10
 
+defaults:
+  run:
+    shell: bash
+
 jobs:
   rustdoc:
     if: github.repository == 'rust-lang/rust-analyzer'