Skip bind port 1 when ip_unprivileged_port_start<=1

Linux can allow to bind port 1 to user.
And `ip_unprivileged_port_start` is 0 on [lima](https://github.com/lima-vm/lima) default vm.

```
1)
Socket#bind on SOCK_DGRAM socket raises Errno::EACCES when the current user does not have permission to bind FAILED
Expected Errno::EACCES but no exception was raised (0 was returned)
.../ruby/spec/ruby/library/socket/socket/bind_spec.rb:38:in `block (4 levels) in <top (required)>'
.../ruby/spec/ruby/library/socket/socket/bind_spec.rb:4:in `<top (required)>'

2)
Socket#bind on SOCK_STREAM socket raises Errno::EACCES when the current user does not have permission to bind FAILED
Expected Errno::EACCES but no exception was raised (0 was returned)
.../ruby/spec/ruby/library/socket/socket/bind_spec.rb:79:in `block (4 levels) in <top (required)>'
.../ruby/spec/ruby/library/socket/socket/bind_spec.rb:44:in `<top (required)>'

3)
Socket#bind using IPv4 using a packed socket address raises Errno::EACCES when the user is not allowed to bind to the port FAILED
Expected Errno::EACCES but no exception was raised (0 was returned)
.../ruby/spec/ruby/library/socket/socket/bind_spec.rb:119:in `block (6 levels) in <top (required)>'
.../ruby/spec/ruby/library/socket/socket/bind_spec.rb:85:in `<top (required)>'

4)
Socket#bind using IPv6 using a packed socket address raises Errno::EACCES when the user is not allowed to bind to the port FAILED
Expected Errno::EACCES but no exception was raised (0 was returned)
.../ruby/spec/ruby/library/socket/socket/bind_spec.rb:119:in `block (6 levels) in <top (required)>'
.../ruby/spec/ruby/library/socket/socket/bind_spec.rb:85:in `<top (required)>'
```

1 files changed, 4 insertions, 0 deletions

diff --git a/spec/ruby/library/socket/socket/bind_spec.rb b/spec/ruby/library/socket/socket/bind_spec.rb
index 0349df84a6..4465a3dafa 100644
--- a/spec/ruby/library/socket/socket/bind_spec.rb
+++ b/spec/ruby/library/socket/socket/bind_spec.rb
@@ -33,6 +33,7 @@ describe "Socket#bind on SOCK_DGRAM socket" do
 
   platform_is_not :windows, :cygwin do
     as_user do
+      break if File.read('/proc/sys/net/ipv4/ip_unprivileged_port_start').to_i <= 1 rescue nil
       it "raises Errno::EACCES when the current user does not have permission to bind" do
         sockaddr1 = Socket.pack_sockaddr_in(1, "127.0.0.1")
         -> { @sock.bind(sockaddr1) }.should raise_error(Errno::EACCES)
@@ -74,6 +75,7 @@ describe "Socket#bind on SOCK_STREAM socket" do
 
   platform_is_not :windows, :cygwin do
     as_user do
+      break if File.read('/proc/sys/net/ipv4/ip_unprivileged_port_start').to_i <= 1 rescue nil
       it "raises Errno::EACCES when the current user does not have permission to bind" do
         sockaddr1 = Socket.pack_sockaddr_in(1, "127.0.0.1")
         -> { @sock.bind(sockaddr1) }.should raise_error(Errno::EACCES)
@@ -113,6 +115,8 @@ describe 'Socket#bind' do
 
       platform_is_not :windows do
         as_user do
+          break if File.read('/proc/sys/net/ipv4/ip_unprivileged_port_start').to_i <= 1 rescue nil
+
           it 'raises Errno::EACCES when the user is not allowed to bind to the port' do
             sockaddr1 = Socket.pack_sockaddr_in(1, ip_address)