Remove .ruby-version and update Gemfile to support multiple versions of Ruby (#36281)

Summary:
This Change remove the need to have a specific version of Ruby installed. We are now supporting a wider range of Ruby versions, starting from Ruby 2.6.10 (the ruby installed on MacOS by default).
We are still using a Gemfile to control the version of cocoapods that needs to be installed.

## Changelog

[IOS] [CHANGED] - Remove `.ruby-version` and update Gemfile to support a wider range of Ruby versions

Pull Request resolved: https://github.com/facebook/react-native/pull/36281

Test Plan:
- Tested locally on RNTester and an app from template, switch across different versions of Ruby
- CircleCI is green on the commit

Reviewed By: cortinico

Differential Revision: D43567660

Pulled By: cipolleschi

fbshipit-source-id: e7edfe5806a898a83ba39cb58b1318ebde56a57c

.gitignore

@@ -105,6 +105,8 @@ package-lock.json
 # Ruby Gems (Bundler)
 /vendor
 /template/vendor
+.ruby-version
+/**/.ruby-version
 
 # iOS / CocoaPods
 /template/ios/build/

.ruby-version

@@ -1 +0,0 @@
-2.7.6

Gemfile

@@ -1,7 +1,7 @@
 source 'https://rubygems.org'
 
 # You may use http://rbenv.org/ or https://rvm.io/ to install and use this version
-ruby File.read(File.join(__dir__, '.ruby-version')).strip
+ruby ">= 2.6.10", "< 3.2.0"
 
 gem 'cocoapods', '~> 1.11', '>= 1.11.3'
 gem 'activesupport', '>= 6.1.7.1'

scripts/update-ruby.sh

@@ -32,23 +32,6 @@ fi
 if [ -z "$VERSION" ]; then
     die "Please provide an installed/usable Ruby version"
 fi
-echo "Setting Ruby version to: $VERSION"
-
-cd "$ROOT" || die "Failed to change to $ROOT"
-
-# do this first, so rbenv/rvm will automatically pick the desired version
-echo "$VERSION" > .ruby-version
-
-# make sure we're using it
-CURRENT_VERSION=$(ruby --version | cut -d' ' -f2 | cut -dp -f1)
-if [ -z "$CURRENT_VERSION" ]; then
-    # rbenv/rvm uses shims, the commands do exist, but do not return a version if misconfigured
-    die "Missing usable ruby, check your installation"
-elif [ "$VERSION" != "$CURRENT_VERSION" ]; then
-    die "Plese use the ruby version you are trying to set: $VERSION ('$CURRENT_VERSION' in use)"
-fi
-
-echo "$VERSION" > template/_ruby-version
 
 rm -f Gemfile.lock
 
@@ -61,11 +44,9 @@ bundle lock
 export GIT_DISCOVERY_ACROSS_FILESYSTEM=1;
 IS_GIT_REPO=$(git rev-parse --is-inside-work-tree 2> /dev/null || true)
 export GIT_DISCOVERY_ACROSS_FILESYSTEM=0;
+
 if [ "$IS_GIT_REPO" = "true" ]; then
-    git add \
-        .ruby-version \
-        Gemfile.lock \
-        template/_ruby-version
+    git add Gemfile.lock
 else
     echo "Detected that you're not in Git. If on another SCM, don't forget to commit the edited files."
 fi

template/Gemfile

@@ -1,6 +1,6 @@
 source 'https://rubygems.org'
 
 # You may use http://rbenv.org/ or https://rvm.io/ to install and use this version
-ruby File.read(File.join(__dir__, '.ruby-version')).strip
+ruby ">= 2.6.10", "< 3.2.0"
 
 gem 'cocoapods', '~> 1.11', '>= 1.11.3'

template/_ruby-version

@@ -1 +0,0 @@
-2.7.6