fix(ci): Pin r-lib actions as a workaround for latest action updates #354

Job	Run time
check (macOS, adbcdrivermanager) / r-check	1m 39s
check (macOS, adbcflightsql) / r-check	2m 25s
check (macOS, adbcpostgresql) / r-check	1m 47s
check (macOS, adbcsqlite) / r-check	1m 50s
check (ubuntu, adbcdrivermanager) / r-check	1m 58s
check (macOS, adbcsnowflake) / r-check	2m 38s
check (ubuntu, adbcflightsql) / r-check	3m 31s
check (ubuntu, adbcpostgresql) / r-check	2m 19s
check (ubuntu, adbcsnowflake) / r-check	2m 38s
check (ubuntu, adbcsqlite) / r-check	2m 39s
check (windows, adbcdrivermanager) / r-check	3m 40s
check (windows, adbcflightsql) / r-check	5m 0s
check (windows, adbcpostgresql) / r-check	4m 59s
check (windows, adbcsnowflake) / r-check	5m 7s
check (windows, adbcsqlite) / r-check	3m 53s
	46m 3s

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